For those with bad battery life....
Install cpu spy. You will likely notice that your phone spends a lot of time at 192mhz when it should be in deep sleep.
I'm looking into this issue but it will take a few days at least. In the mean time, try using the app "DS Battery Saver". This app forces the phone into deep sleep when the screen is off. I've been using it for a few hours and it works amazingly well.
Do you know how it functions if I am downloading a file (latest beta rom) when the screen goes black? Is it going to stop/pause/screw up my download?