I was wondering if it would be possible to calculate some kind of a metric for the speed-of-publication for each journal. I'm not sure submitted and accepted dates are available for all papers, but I noticed in XML data there are fields like the following:

<PubMedPubDate PubStatus="received">
                <Year>2011</Year>
                <Month>12</Month>
                <Day>13</Day>
            </PubMedPubDate>
            <PubMedPubDate PubStatus="accepted">
                <Year>2012</Year>
                <Month>4</Month>
                <Day>2</Day>
            </PubMedPubDate>
            <PubMedPubDate PubStatus="aheadofprint">
                <Year>2012</Year>
                <Month>4</Month>
                <Day>2</Day>

Is there any type of tool which calculates the average time from which a paper is submitted to the time it is published? Or is there a way that this kind of information could be abstracted from this database to give a aggregate estimate of turn-around time? Has someone already done this? And--not to get too off topic--but what other kinds of measures would be useful to evaluate the degree of burden in submitting a paper?

EDIT: Pierre really took this to the next level in answering this question. The table he produced is very interesting and informative and his complete results are posted at figshare. Check it out. Or try it out.

The following java program parses a pubmed XML from stdin and prints the difference of days beteen "received" and "accepted":

import java.io.InputStream;
import java.util.GregorianCalendar;
import java.util.concurrent.TimeUnit;

import javax.xml.namespace.QName;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.events.Attribute;
import javax.xml.stream.events.XMLEvent;




public class Biostar54473
    {
    private static class PubMedPubDate
        {
        int year;
        int month=-1;
        int day=-1;
        @Override
        public String toString() {
            String s=String.format("%04d", year);
            if(month!=-1)
                {
                s+="-"+String.format("%02d", month);
                if(day!=-1)
                    {
                    s+="-"+String.format("%02d", day);
                    }
                }
            return s;
            }
        long getTimeInMillis()
            {
            GregorianCalendar cal=new GregorianCalendar(
                    year,
                    month==-1?0:month-1,
                    month==-1 || day==-1?
                    1:day);
            return cal.getTimeInMillis();
            }
        }

    private void parse(InputStream in) throws Exception
        {
        XMLInputFactory factory = XMLInputFactory.newInstance();
        factory.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.FALSE);
        factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.FALSE);
        factory.setProperty(XMLInputFactory.IS_COALESCING, Boolean.TRUE);
        factory.setProperty(XMLInputFactory.IS_REPLACING_ENTITY_REFERENCES, Boolean.FALSE);
        XMLEventReader r= factory.createXMLEventReader(in);
        String PubStatus=null;
        PubMedPubDate curr=null;
        PubMedPubDate accepted=null;
        PubMedPubDate received=null;
        String MedlineTA=null;
        String pmid=null;
        String ArticleTitle=null;
        QName attPubStatus=new QName("PubStatus");
        while(r.hasNext())
            {
            XMLEvent evt=r.nextEvent();
            if(evt.isStartElement())
                {
                String name=evt.asStartElement().getName().getLocalPart();
                if(name.equals("PubmedArticle"))
                    {
                    pmid=null;
                    accepted=null;
                    received=null;
                    MedlineTA=null;
                    pmid=null;
                    ArticleTitle=null;
                    }
                else if(name.equals("ArticleTitle") && ArticleTitle==null)
                    {
                    ArticleTitle=r.getElementText().trim();
                    }
                else if(name.equals("PMID") && pmid==null)
                    {
                    pmid=r.getElementText().trim();
                    }
                else if(name.equals("MedlineTA") && MedlineTA==null)
                    {
                    MedlineTA=r.getElementText().trim();
                    }
                else if(name.equals("PubMedPubDate"))
                    {
                    curr=null;
                    Attribute att=evt.asStartElement().getAttributeByName(attPubStatus);
                    if(att!=null) PubStatus=att.getValue();

                    if("received".equals(PubStatus))
                        {
                        curr=new PubMedPubDate();
                        received=curr;
                        }
                    else if("accepted".equals(PubStatus))
                        {
                        curr=new PubMedPubDate();
                        accepted=curr;
                        }
                    else
                        {
                        curr=null;
                        }
                    }


else if(curr!=null && name.equals("Year"))
                    {
                    try { curr.year=Integer.parseInt(r.getElementText().trim()); } catch(Exception err) { curr=null;received=null;ok=false;}
                    }
                else if(curr!=null && name.equals("Month"))
                    {
                    String month=r.getElementText().trim().toLowerCase();
                    if(month.equals("jan") || month.equals("january")) month="1";
                    else if(month.equals("feb") || month.equals("february")) month="2";
                    else if(month.equals("mar") || month.equals("march")) month="3";
                    else if(month.equals("apr") || month.equals("april")) month="4";
                    else if(month.equals("may") || month.equals("may")) month="5";                    
                    else if(month.equals("jun") || month.equals("june")) month="6";
                    else if(month.equals("jul") || month.equals("july")) month="7";
                    else if(month.equals("aug") || month.equals("august")) month="8";
                    else if(month.equals("sep") || month.equals("september")) month="9";
                    else if(month.equals("oct") || month.equals("october")) month="10";
                    else if(month.equals("nov") || month.equals("november")) month="11";
                    else if(month.equals("dec") || month.equals("december")) month="12";
                    try { curr.month=Integer.parseInt(month); } catch(Exception err) { curr=null;accepted=null;ok=false;}
                    }
                else if(curr!=null && name.equals("Day"))
                    {
                    try { curr.day=Integer.parseInt(r.getElementText().trim()); } catch(Exception err) { curr=null;accepted=null;ok=false;}
                    }

                }
            else if(evt.isEndElement())
                {
                String name=evt.asEndElement().getName().getLocalPart();
                if(name.equals("PubmedArticle"))
                    {
                    if(received!=null && accepted!=null)
                        {
                        long n=accepted.getTimeInMillis()-received.getTimeInMillis();
                        System.out.println(
                                pmid+"\t"+
                                ArticleTitle+"\t"+
                                MedlineTA+"\t"+
                                received+"\t"+
                                accepted+"\t"+
                                TimeUnit.DAYS.convert(n, TimeUnit.MILLISECONDS)
                                );
                        }
                    ArticleTitle=null;
                    MedlineTA=null;
                    pmid=null;
                    curr=null;
                    received=null;
                    accepted=null;
                    }
                else if(name.equals("PubMedPubDate"))
                    {
                    curr=null;
                    }
                }
            }
        }
    public static void main(String[] args) throws Exception
        {
        System.out.println("#pmid\t"+
                "ArticleTitle\t"+
                "MedlineTA\t"+
                "Received\t"+
                "Accepted\t"+
                "DiffDays"
                );
        new Biostar54473().parse(System.in);
        }

}

A 'verticalized' example for a few papers containing the word "Next generation Sequencing" in the title. You can read this in R# or whatever to get some stats about a journal, a subject, etc...

$ javac Biostar54473.java && cat pubmed_result.xml | java Biostar54473

>>>    2
$1    #pmid           23020966
$2    ArticleTitle    Transcriptome analysis using next-generation sequencing.
$3    MedlineTA       Curr Opin Biotechnol
$4    Received        2012-07-04
$5    Accepted        2012-09-04
$6    DiffDays        62
<<<    2

>>>    3
$1    #pmid           23000871
$2    ArticleTitle    Understanding pathogens in the era of next generation sequencing.
$3    MedlineTA       J Infect Dev Ctries
$4    Received        2012-09-13
$5    Accepted        2012-09-14
$6    DiffDays        1
<<<    3

>>>    4
$1    #pmid           22994565
$2    ArticleTitle    Accurate variant detection across non-amplified and whole genome amplified DNA using targeted next generation sequencing.
$3    MedlineTA       BMC Genomics
$4    Received        2012-01-30
$5    Accepted        2012-09-20
$6    DiffDays        233
<<<    4
(...)
>>>    253
$1    #pmid           18604217
$2    ArticleTitle    Alta-Cyclic: a self-optimizing base caller for next-generation sequencing.
$3    MedlineTA       Nat Methods
$4    Received        2008-03-10
$5    Accepted        2008-06-02
$6    DiffDays        83
<<<    253

>>>    254
$1    #pmid           18262675
$2    ArticleTitle    The impact of next-generation sequencing technology on genetics.
$3    MedlineTA       Trends Genet
$4    Received        2007-11-15
$5    Accepted        2007-12-17
$6    DiffDays        32
<<<    254