Are these real usability tests or do you just take people from the street and ask them to perform certain tasks on a certain UI (or variants of a UI)? This "people from the street"-approach is the one I know and it doesn't give you any usable input except when designing websites that are expected to be used only once in a while.

A real usability test would maybe take into account some first time users, but focus on experienced long-time users.
The problem with what companies define as "usability" these days is they tend to focus on the short-time experience. That's logical from a commercial point of view (you have to attract those who use the device only for a short time, like journalists, or only try it once in the shop), but it makes applications inefficient for every day use. IMHO, efficiency in every day use is much more important than intuitive and easy first-time use.


??? the N810 does have a D-pad. Doesn't yours?