I fully understand that a qPCR is required in a microarray experiment, because of many reasons. You are playing with hybridizations and this can lead you to run in many kinds of problems (cross-hybridization, background, false hybridization, etc)
But to me, RNA-Seq is quite different. You are using actual sequences that are mapped to your references. You can also control reads that are not mapped uniquely. And this means actual data that cannot appear as an artifact, thus making me think that maybe qPCR is not required.
In addition, qPCR is not prone to be a perfect technique. However, a lot of papers show validation of RNA-Seq data using qPCR, and I am wondering which is the reason for that. I understand that it depends on several facts, like when you are mapping to cds only (where you use to run the qPCR) or to 3' UTR as well that can lead to a different result since 3' UTR expression can be quite variable sometimes..
Do you think that RNA-Seq is actually required to validate RNA-Seq data?. What are your thoughts ?