I had the same problem and realised that BROWSERD was using 90+% of the CPU after using the default web browser.

I managed to realise this after inputting "top" in the Xterminal. Obviously it seemed very false to have broswerd continuously eating up the CPU... and killing the application would not work until you open a web browser again.

It did not make a difference even when uninstalling all applications such as facebook, ap news, weather etc etc...

The solution was quite simple. It seems that JAVASCRIPT was automatically enabled on the PR1.2 update and disabling it eliminated my problem.

CPU got working back to normal, battery did not drain immidiately and the body was not heating up, quite obvious that the CPU was not being overloaded for nothing.

Hope this helps coz it was freeking me out oh and I did flash a couple of times, what a waste of time!