I would say Gambit for most likely to surprise as they do seem to have engaged best with their new IGL and thats been to good effect. Not sure on Liquid especially, SK are the favourites but have been absent at times
I know they didnt pull it off for Summit, when I wrote that about them but they just won Dreamhack Lan which is an awesome turn for them. Very close game vs G2 who were not looking weak at all. Triple Overtime on Nuke I think it was which they just about let slip and I thought that was it really, they wouldnt seal the deal after that but somehow they held on and came back to win the series. Excellent job by them, I like it when the seeming underdog wins but in this case kudos goes to Zeus I think who has really added to the teamwork, leadership and direction of the team weaponising the skills of course already very talented experienced capable players.
Hope Zeus feels very much better about being almost literally laughed out of Navi, I'm sure they didnt really respect him enough from what I saw of the team talking and you cant lead 4 ego driven 'best in the world' players without some mutual respect for your gameplan.