I've been having a lot of problems with Gtalk as well. I assumed it had something to do with the "wifi bug" as it appears to be worse when I'm using wifi and better when using 3G.

The similarity to your situation is the fact that I also have a notebook using wifi (and previously connected ) to Gtalk.

skype seems fine .... but gtalk keeps bringing up that error....
"unable to connect to one or more accounts"

then a few seconds later, it connects fine.

Every few minutes, I get the error again (say every 5-15 mins) and that message continually popping up runs the battery down.