I've had nothing but Wifi issues since Froyo.
First I had the leaked Froyo from Mydroidworld with the p3Droid kernel with supposed wifi fix. My wifi has been malfunctioning since then. I've used all the newest basebands. Used the "updated" leaked Froyo with p3Droid's kernel (125-1200 which had amazing battery life compared to bb Froyo). Then switched to bb Froyo .1 with chevy's froyo 250-1200 and to bb Froyo .2 and .2.1 with no change. I've wiped 3 times (data and cache). Have tried the stock bb kernels, chevy, p3Droid, all the same results.
It will be connected and then as soon as I start to download a file or view a page with any real amount of space it disconnects. The wifi symbol disappears from the notification bar and will stay disconnected for around 20 seconds. Rinse repeat.
As far as my wireless I have the Netgear WNR-3500 Wireless N router running on channel 11 with WEP encryption.
I feel if we post our stats as far as roms, routers, and kernels we may find a fix. And if need be I can post a nandroid etc.
Also, I wish bb froyo didn't automatically install apps to SD, and would allow me to restore my apps from the market automatically like it used to
Also Froyo has been made to use 125mhz far better than anything before it, so IMHO there is no excuse for having to use 250mhz.
And I'm sorry if this all has a negative tone, it's just that I've been a BB user since the day I brought my Droid, using Bugless Beauty and on. I've never had any issues with any release till now, and I just feel like things are being rushed out now without testing and not in a clean fashion. I just feel very let down.