My n800 is slightly over one year old, and the battery performance has recently dropped. I now get only 1.5 to 2 hrs of continuous usage from it (i.e. surfing or watching video) after a full charge. My experience with other Lithium-Ion batteries is that they last at least 2 years before declining.

Note: I haven't installed any new applications recently and didn't upgrade to Diablo.

I'm curious how long other n800 owners' batteries lasted before they noticed a performance drop.