I didn't care for the G1 much when I played with it (I didn't like that weird sort of hump at the end when you have it in horizontal mode). The iPhone is seductively tempting with all its apps ... I really do like it, but I sort of don't want to switch to AT&T to get it.
This, though ... this is coming from Sprint, and I've heard they have a cheaper data plan than most, and it's Palm. Despite the new OS, I'm sure that they'll offer a means of recognizing current contact information and importing it (or some third party developer will).
Also, I think it's the prettiest phone of its type that I've seen. It looks very sleek. Palm has needed a comeback device, and this could be it.
I'm at least a year away from considering a new phone purchase, and I'll be very interested in seeing the market competition at that time.
EDIT: Video of a live demonstration of the device:
Palm Pre UI demo (1 of 5)
Palm Pre UI demo (2 of 5)
Palm Pre UI demo (3 of 5)
Palm Pre UI demo (4 of 5)
Palm Pre UI demo (5 of 5)
After watching these videos, if it works half as well as it does in this demo, I'm like: "iPhone who?" I'm impressed with the elegance of the user interface. I could see myself going into full geek squee over this if the reality is anywhere near the presentation.