bumpski - 11:08 am on Nov 1, 2010 (gmt 0)
I believe that it is all or nothing.
My mistake! What I was referring to was adding the AdURL of a flash ad to the Competitive Ad Filter list.
With the text ads you can "view source" of the Adsense ad iframe and search for the "adurl=" and then block the domain. With "Image" ads especially flash I don't see a way to do this. (Adsense probably prefers it this way anyway).
Link unit are very poor as conversion compare to ad unit for advertisers.
At least for me Link Units produce more than 30% of my earnings. Must depend on your topic and content. Try putting a Link Unit at the bottom of your pages, near the center, you might be surprised!
Here's a tip; have a "bottom" and "top" link on all your pages (top doesn't work in firefox?)
Oddly enough having one of these repetitive display/image/branding ads might drive clicks to an adjacent Link Unit. (Does that break the TOS, I don't think so.)
These image/display/branding ads show over and over again on multiple pages as visitors traverse the site. They become a waste of advertising space. (And for small highly targeted sites the CPM ads seem to produce substantially less earnings than the PPC ads.)