Who still uses gene expression microarrays? I do and lots of other people do. And even though it’s pretty clear that RNA-seq is better, as long as it’s more expensive — and it probably still is for many combinations of microarray and sequencing platforms — the trade-off between the technical variability and sample size should still favour microarrays. But the breaking point probably occurs about right now, and I’m looking forward to seeing lots of sequencing based genetical genomics with splice-eQTL, antisense RNA-eQTL and what not! But then again, the same might happen for RNA-seq in a few years: I hope people stick with current generation massively parallel sequencing long enough to get decent sample sizes instead of jumping to small-N studies with the next technology.