AMD has a cute page at its 50×15 project, which has counters with estimated counts of the world population and the estimated number of Internet users. The user number grows a lot faster than the population number.
50×15's purpose is to draw attention to the hope that half the planet will be connected by 2015 — a status that AMD says on current trends won't happen until 2030 unless someone ramps things up.
As of this posting, world population is about 6,607,372,000; internet usage about 1,140,247,000; and penetration at 17.25%. [corrected]