I was just logging in to ask the same question. A lot of really legit sites - and when you test them against other vendor reputation sites, they are fine. I am planning on turning in a support ticket today for this as I think there is something wrong with TrustedSource's ratings. I'm beginning to lose faith in their accuracy.
Mostly, when I submitted those sites to trustedsource, they came back with a modified rating, but given the volume of tickets that we were receiving I punted and changed our rules so that we still Use URL.IsHighRisk, but rather than using URL.IsMediumRisk I'm using URL.Reputation<Default> greater than 30.
Screws up my URL Checker unless the folks using it know to look at the Reputation Score rather than looking for Unverified/Minimal/Medium/High, but we already have quite enough to submit to trustedsource, especially in the realm of Akamai netblocks that they insist as classifiying as Residential IP Addresses.