The most important surface change is probably the fact that it doesn't have the flip-open keyboard like the P990, but that's something you'll have to play with yourself to see if you prefer. Otherwise, it seems like Sony's got a great upgrade here with the P1. And yes, they've answered everyone's question about what they'd do when the numbers get to 999—wrap around again back to 1.
Bigger shots after the jump.
Press Release [Sony Ericsson]