I am running .52, and I can no longer get google talk to work. It always tells me that my user name and password do not match. I'm using the same ones that I do on my desktop computer with no trouble. I even downloaded the latest version of google talk, and it does not fix things. I know it was working even after I updated to .52 so I don't think it is the OS.
OK, so as I suspected, it is not a known version issue. Yup, I've had to pull the battery several times, and none of them fixed it. Maybe I need to get rid of my google-talk account and re-create it...