Blocking Unwanted Ads in Adsense
A post at REvenews suggests that the elevated limit of blocked urls (to 500) in Adsense, should almost eradicate unwanted ads.
REvenews further suggest culling the lower value ads to maximise revenue. This tactic is a little bit contentious as you maybe inadvertantly blocking highly relevant and optimised ads. Google have also voiced their concerns in a recent post at Inside Adsense, but then I suppose they would do, wouldn't they!!