Someone in dyxum tested the adaptor and mentioned that motorised alpha lenses can AF on nex. Even 3rd party motorised lens (he tested sigma 24-70 HSM)
http://www.dyxum.com/dforum/nex-and-adaptors_topic62746_page3.html
Im guessing that some motorised alpha lenses do work, but not all. Thus to prevent potential complains from customers, sony decided to announce (or even disable af in release firmware) that af is not working yet, until they can get it to work 100%.
Personally i wouldnt mind if it works with only a few lens for now, at least it'll allow nex users more choice.
I could mount the 30mm or 50mm f1.8 on the nex and use it as a portrait camera