I have to wonder if Esri will need to make more progress with porting functionality from 3.x before we see more literature. There is still a bit of important functionality that needs to be ported, not to mention some bugs and intricacies resolved in 3.x that have cropped-up again in v4.
I like the progress on the one hand, but on the other, we have invested years into creating a mature product based upon the 3.x line, Esri's suggestion to "re-write" rather than port 3.x-based applications really stings! IMHO, API upgrades shouldn't be so obtuse, but I understand the reasoning, and it is certainly not unprecedented. We re-wrote our mapping app from Silverlight (not even Esri-based) before switching to the JSAPI a few years ago.