Supposedly it will incorporate a new type of battery with around 10x the capacity of the current one.
I understand the need for this, but not a selling point for me. Both me and the missus only use it at home, so a power point is never far away. We only bought it...well, i couldn't really tell you why, she wanted it for Christmas a few years back, so i bought! (gen 1 ipad)
The res on the screen sure is something to see, but since i'm (we) am not a power user, it certainly is not enough to justify the jump. I could really see us sticking with the gen 1 for as long as it will work. (I hope my missus doesn't read this though, or there will be an ipad "accidentally" dropped in the bath tab by tomorrow!)
I'm actually waiting on iphone 5 for my next idevice upgrade. I didn't bother with the 4S since just about all of Siri's (or at least what i wanted) functionality is disabled here in AUS, (damn or accents) so it had nothing to make me ditch my iphone 4. If what i have read about the screen size for the iphone 5 is correct, then i'll grab that one, or move to an Android HTC if it fails to impress.