Don't have sources by me right now but I'm pretty sure the processor in this one is less power hungry (than in Pre or Pre Plus) which coupled with new version of the OS (where one of the goals was to optimize it power usage wise) should give more battery life. However, Pre 2 is sold only in France at this moment and I don't think we have a real world test of the battery to prove anything (or at least I haven't seen it).
Also, I have the original Palm Pre which at first barely made it through one of my days. However, after getting the UberKernel on it and undervolting it conservatively, not only is it faster (1GHz) but it easily lasts throught the day (and I really use my Pre, connected all the time to either WiFi or 3G). I'm thinking if I didn't use it so much it could easily last even two days because sometimes it's not completely drained at the end of the day but I still charge it daily (and given that some smartphone users I know with non-Palm devices don't have a habit of being constantly connected to the internet like I do, if I played that way, I definitely wouldn't have to charge it daily).
I have the phone. The battery life is not good. After 7 hours use it has 35% battery life left. I solved this problem by getting two small USB batteries - one small for my pocket and a larger one to keep in the car. Even with the battery issue, this is the very best phone I've used.
It's not great - about a day; but there are some easy solutions. I have a Touchstone in my car and at my desk, and I just leave it on that when I'm not mobile. I also keep a couple of spare charged batteries in my purse just in case. The spares (OEM) were less than $5 each, and they're easy to swap out.