Anybody else having issues with battery life since 3.1.2?

I have a fairly new, 2 months, 3Gs, something seems to have happened recently, after 3.1.2 upgrade I JB'd w/Blackra1n. Now it's almost as if I can watch my battery drain, it's been on now for 1/2 hour and already down to 96% and I haven't even been using it. Yesterday I was out and about, used the camera for a few pics, a few quick videos and mms, next thing I looked and it was at 15%.

The other morning I turned it on, had it on my desk for a few hours and when I went to use it, it was completely dead!

I don't know if it's really an issue with the battery or maybe I should wipe clean, restore and re-JB?

Any thoughts appreciated.

Chip