It's possible that Nokia made the change to a 3.5 inch screen in order to make this thing more pocket-able (and gain more acceptance.) I almost never saw a 800/810 review or reference that stressed the pocket-able factor. People always just lump them into the Tablet or MID category. In theory and in Nokia's marketing, the 800/810 were pocket-able devices, but in actual use I think they were just a little too big for most people's pockets.