PokerRoom and its skins are the only ones that run on Mac now (its web based java app), all others require install on your machine. Even Poker room's instaled version won't install on a Mac IIRC, and you lose a buncha chat features and flexiblity.
http://www.fullcontactpoker.com/ is one skin of Poker Room and the community and related bonus material for it being Daniel Negreanu's site are quite good. Not to mention he is Canadian and a major hockey fan.