I've been impressed with, in no particular order:
Taylor Walker, Dangerfield, Hill (Freo), Ziebell, Rioli (though that's no big surprise), Grimes, Bennell, Dawson (great credit to him for fighting back), Vince - I think he's quality, Goddard is finding his feet, Dal Santo is proving a few people wrong, Tredrea, and NO ONE ELSE... just kidding