Recent Macs have a wifi chip that requires WME/WMM extensions (Wireless Multimedia) in most cases. For most APs it will have issues if these are switched off. Rumor is it's a chipset thing not a software thing.
Got any more information on that? I usually leave WMM off on account of it being extra complexity that doesn't seem to make anything work better, and I haven't noticed any particular issues with my six month old rMBP. Which chipsets are supposedly afflicted?
(side note: I wish they'd never stopped using Atheros WiFi.)
It was a while back and The Goog is not delivering, but I do distinctly remember this being an issue and that enabling this extension fixed it. But maybe only certain MBPs are affected.
