In response to popular request, block domain ads looks to be coming, along with other blocking features.
I have reported at the Search Engine Roundtable that some AdWords advertisers are now able to block categories of sites, plus they are able to block domain ads and error page ads. Back in August, Google told us that AdSense For Domains Opt Out Coming To AdWords Advertisers. It appears that some advertisers are now able to take advantage of that feature.
The Site Exclusion features, which I personally do not yet see myself, reportedly include:
Block sites by domain, sub domain, or fold [...]
Related Topics: Channel: SEM | Google: AdWords | Search Ads: Domaining