I go along with the others get the Safari Extension Adblock, it works really well. I also use the extension Ghostery which is more of a privacy thing. On the Macrumors site it blocks Chartbeat, Google Analytics, Netshelter and Quantcast. On some sites it blocks many more trackers.
Both available from Safari menu - Safari-Safari Extensions.
It's pure proxy based. I had to do lots of custom definitions. Does not work for me at certain job sites. The actual proxies get all screwy and it just fails and dies. So I moved on.