No, what it means is that 10% of the all hits to this site running a resolution lower then 1280. The server doesn't peg a resolution to an IP and assume that resolution every time that person visits. It just tracks the resolution of EVERY visitor every time they visit.
So no, those 10% of the people can't be doing 50% of the browsing (ex).
Check out here: http://www.whatismyscreenresolution.com/








