My rankings..
1) Pyramid -- Has always been a favorite, and it's true to the originals that preceded it.
2) MG - In the same vein of Pyramid, true to the originals. Went back to the tried-and-true '70s game, and not any enhancements or modifications.
3) CFF - I don't get a chance to see the syndicated one much, and it's nice to see Feud "on a network".
4) CS - Some interesting modifications - 1 round of 10 cards. However, I've always been a fan of the push rule in Money Cards, which is gone.
5) PYL - The first part, old school PYL? Golden. The second half bonus round? Unnecessary.
6) TTTT - never got into previous versions, so not really motivated to watch the new one.