A lot depends on your planned use. Palms measure battery life in days. iPaq and other pocket PCs measure it in hours. Color is nice . . . but it eats power snoot raw.
But, between iPaq and Clie, I would probably pick HP's Jornada.
The one to watch is the HandEra . . . and the first PDA that has a standard CF slot will really have an advantage with the 1 GB Microdrive that can be used with it.