From my experience, there's definitely a shortage of competent bioinformaticians. There are plenty of people who have caught onto the demand and will advertise themselves as bioinformaticians and land positions when the gullible hiring managers don't know how to properly vet them. I've seen plenty of people with the job title who are totally lost if their favorite tool fails to answer the question. You gotta know how to code and think critically to do this job. Straight up.
If you really want to know about the shortage of competence, be part of the hiring process for a widely-advertised bioinformatics position. You'll get a lot of impressive resumes (some of them word-for-word identical sans the contact info), and just as many hilarious/awkward technical interviews (if you're lucky enough to get the go-ahead to do such a thing).
Another major problem in the field is the perception that one bioinformatician is enough to solve all the IT problems. At my last position I was in charge of server administration, desktop support (can't access facebook, help plz), application support (including deploying Galaxy on a cluster), repairing my boss' kid's feculent laptop, answering random PI data questions, giving seminars on how to do basic analysis, lab automation, website/web application development and administration, and being pimped out to other departments to curry political favor, explaining FASTQC to the 814th PI who soiled themselves because they saw a red X OMG OMG, oh yeah, and actual bioinformatics!
*breathe*, *count to ten slowly*
Note: I love bioinformatics and I think I'm lucky to be able to work in the field. But employers, if you want to attract and retain bioinformaticians, make a focused job description and stick to it once you fill the position.