I would say that www.flyertalk.com is probably the most comprehensive. www.milepoint.com is well on its way - still a lot smaller but a lot friendlier.

Wes, how have you found Bank Direct? I was going to do that but they charge a monthly fee of something like $14 now. Another one that wasn't mentioned is Fidelity - if you don't currently have an account with them, you can open an account through a link and get 50,000 AA or United miles if you fund it with $100,000 (you can withdraw almost immediately) and if you do it right you can also get 50,000 Delta miles for the same funding.

I would agree that credit card signup bonuses is the best game in town now for points / miles.

For the Carlson (Radisson, Country Inn & Suites, Park Inn) promotion - I'm doing it to transfer the points out to AA miles (effective cost is $0.008 / mile).