I have a gen 1 early 2006 "thigh burner" model and I'd be lucky to get 1.5h doing anything that requires the screen to be on... Now I got really, really tempted to upgrade.

Same here. My Rev. A core duo MBP gets about the same, 1.5 hours. Problem is that once the battery hits 20% capacity it will shutdown the machine at any moment.

I've got an entry level unibody macbook, just the 13" one, and I consistently get between 4 and 5 hours battery life. This is browsing and development using netbeans (not the most lightweight ide ever designed). For lighter use I'll occasionally see 6+ hours, but that's often when I'm doing something else at the same time.

Exactly - I almost don't care about battery life because they all break down quickly anyway. If Apple managed to solve THAT problem, they are on to something, though. While atm I count on there being power sockets mostly everywhere, being freed from that might open up new use cases.

Would it be possible to swap out the battery for one of the new ones? I'm in the same boat.

No. The new batteries are non-removable, and wouldn't fit.

2:20! do you have the dual graphical cards? I find that switching to the low power graphic cards will give me around 5 hours, but my mbp is only two months old. I'd be sad if it would deteriorate to 2 hours in just half a year.

i'm always on the lower power GPU. for clarification, i can get around 4 hours with wifi off (on planes).