Some interesting thoughts. I'd have put TGP's and linklists into the same catagory being that they're really the same idea. (I know 10 of you are itching to say "Link site traffic is better!" - but notice who Tommy and Greenguys top referrers are)
My second catagory would be free content sites - including galleries (as in TG's)
Third would be no content sites - CJ's and pages of nothing but ads.
And fourth would be actual paysites.
As for your question I think everyone thinks they're in the most profitable end of the biz.
But really though, I think most of us are working in different areas. I run a TGP, a CJ, and 2 (kind of) content sites.