I know this bug has affected a few people, so basically there was an issue with the Broadcom driver that's been recently fixed:
http://android.git.kernel.org/?p=platform/system/wlan/broadcom.git;a=commit;h=5a838529e6197475cbe8f5a4557fbd31f90586a6
It was affecting some N1 owners, myself included, and a few friends. Basically if you've had trouble with your Wireless and your MAC doesn't start with 00: then this is for you.
Grab any of the latest CM6 nightlies from 07222010-135717 and the fix is included:
http://mirror.kanged.net/cm/nightly/passion/
This also resolves the issue where if your screen is off, you get *zero* traffic to your N1
Just thought I'd post the heads up here, in case it's of use to any other fellow N1 owners :)
Cheers
Chill.