Jun 19
Advertisers can now exclude up to 20 specific IP addresses per campaign.
This is a good step in preventing click fraud (from competitors) and accidental clicks (from within the company/ad agency). You can now also block MFA sites.
Nevertheless this new tool should be used wisely to avoid that you ban wide ranges of potential visitors.
More Info: https://adwords.google.com/support/bin/answer.py?answer=61492
Upcoming: eBay Ads and listings exclusion tool for AdSense 
advertising Adwords click fraud Google IP exclusion Made for Adsense MFA Search engines 
