I have used http://developer.apple.com/bugreporter/ for more than 30 times in the past 4 months with some major bugs in the APIs and Xcode and the infamous bug - Mission Control. I haven't really research Mac developer forums for this issue which has cropped up recently.
But I'll take your word. I better ask this on dev forums.
I was having that issue... I disabled air video player server app running in the background and it hasn't dropped since. I thought it was IPV6 causing it, but disabling that didn't help. No wifi drops since I uninstalled that AVP server app. P.S. I did a clean install of lion
'15/07/2011 17:17:23.740 airportd: _doAutoJoin: Already associated to dethmaShine. Bailing on auto-join.
15/07/2011 18:20:01.000 kernel: AirPort: Link Down on en1. Reason 8 (Disassociated because station leaving).
'
It looks like its getting disassociation packets and is trying to disconnect itself.
It started happening after the GM build. Does some one have a temporary solution to this?
Mine seems to drop whenever a TimeMachine backup begins. Eventually it will reconnect but it's a pain in the ass. Currently have TM disabled during the day.
I've got the exact same problem too! Wifi keeps dropping right after I upgraded to Lion. I suspect that the Airport drivers got changed and there's a bug somewhere, making it very susceptible to interferences.