KISSmetrics has a post explaining how the tracking works. http://www.kissmetrics.com/how-it-works They claim that simply using AdBlock is enough to defeat the tracking. They also claim "KISSmetrics has never, and will never, share anonymous customer activity of what people did on customer A’s site with customer B."
hazza for adblock, as much as i like to see the legislature and courts support privacy this is fundamentally a technological problem.
Compare with spam. Technological solutions have reduced the problem, but to virtually eliminate it requires global law enforcement.