Bioware has confirmed no controller support due to "development time constraints" (BS). However there's a profile for Pinnacle Game Profiler that I've been using for ME2 for the past week that works really well (and perhaps better than default 360 controls).
Basically the 8 quickslots have been mapped to RB, X, Y, and B so I really never have to open up the power menu except at the beginning of a mission to assign powers to the quickslots.
Controls: LT - Aim RT - Fire LB - Power Menu RB - Quickslots 1/2 (hold) X - Quickslots 3/4 (hold) Y - Quickslots 5/6 (hold) B - Quickslots 7/8 (hold) A - Action/Sprint/Cover LS - reload RS - melee BACK - holster START - Pause/quicksave (hold) DPad left - squadmate 1 command DPad right - squadmate 2 command DPad up - Form up squadmates DPad down - cycle weapons
PGP is $25 but has a 30 day trial (with a time limit per use during the trial). I thought it was worth it for ME3 alone since I don't want to settle for inferior console hardware/graphics, but I'm no KB&M player.
I made a mistake above: Y is quickslots 3/4 and X is quickslots 5/6. The reason being is that I reserve the first four quickslots (RB and Y) for Shepard's powers and then the remaining four (X and B) for the squadmates'. Just felt better for me that way.