correct me if im wrong but i believe the native resolution is the highest resolution the screen can support. I used to think 1280 x 1024 on my old desktop was enough but ever since i got my 9300 (w 17inch screen) i cant imagine using anything below that (given the screen may be closer to my face, but still, if i got a larger screen i definitely would want it to be uxga)
edit: for games i could understand 1280 x 1024 being enough, but if you use other programs that could benefit from the extra screen real estate (3d modeling is an example) then i dont think 1280 x 1024 is enough. Also, after using 1920 x 1200, i think everything looks so big (desktop, text, whatever) when going to a lower resolution on a 17 inch lcd.