I've been watching this thread the past few days. I'll comment on all of the different ones below.
As far as .us and .biz domains, yes I know that almost all of them are blocked via Yahoo's quality_block flag. This is across their entire network. I have talked to some of the team who personally decided to block .us and .biz and their reason was that every domain that had any traffic was mostly arbitrage. They had run some TQ scores by cctld/gtlds and anything that was really bad they got rid of. They told me that .us and .biz were blocked because of this reason. I then went to Neulevel/Neustar and told them about it and put them in contact with Yahoo. I know they have at least talked to Yahoo because Yahoo mentioned it to me. But I am not sure where it went after that. I think the blocking of .us and .biz domains was a bad decision.
Yes, Google bans a lot more domains that most people think. And guess where most of that traffic goes? Yahoo.
More people noticed that domains were getting blocked, banned, etc... Because we made that information available to our customers. I thought it was the right thing for us to do. Sure we have gotten a lot of grief since then from our customers side and even from Yahoo. But it was the best thing for our clients.
In Yahoo's world, "banned" usually means a domain did something it wasn't supposed to do. Like arb or really low TQ scores. Yahoo has been banning individual domains that do arb, arb like tendencies, or very low domain level TQ scores. "quality block" is when a domain has too many dashes, too many numbers, or is an extension Yahoo doesn't like, for example .us and .biz. "restricted" is when a domain can be two things and Yahoo has decided it's easier to just require us to put their keywords on a domain, for example applepicking.
Some of the domains that have been mentioned on here, I have checked and submitted them to Yahoo for re-checking.
Donny