I just got mine used yesterday, but I do find the battery life not as good as my Eris. The battery isn't the original, I can tell. It's very generic looking and doesn't say Samsung anywhere on it, just i9000 at the bottom with a serial number above it.
This is a tide-me-over phone. I picked it up for $70. I was thinking about a Revolution but the speed won't be any different really. I'd just be upgrading for the front facing camera, and LTE.
Known as Stonent on XDA