I recently sold my 360 and am going to be playing this on the PC but I've heard that there is no gamepad support on the PC version of the game.  Is that actually true and if so how does the keyboard and mouse support actually feel?  I played the first game on the 360 and think that it might feel a little weird having to go and play the game without a controller seeing as I'm not a huge PC gamer and a 3rd-person shooter just sounds sort of weird with that control scheme.  Is it still worth playing on the PC with the mouse and keyboard scheme?...not that I have much choice now I guess.

Nope, no gamepad support at all. Keyboard control clashes a bit with the GUI (this time they didn't bother to change anything), but eventually you get used to those gigantic buttons and fonts. It's not a big deal, really.

Grab xpadder. It's not perfect by any stretch but you can map the pad so that it's nearly perfect, and just have to get used to a few things being different than the 360 version.
 
Have the same issue as I just didn't play games when i was younger and have only ever really used consoles up until a year or so ago.

There are a few GUI annoyances (specifically the squad selection and codex), but the shooting feels great and planet scanning is much faster.

I have the PC version and the game just FEELS like it was ported from a console.  It's still ME2, but with mods and the keyboard mapping is pretty solid.

I was going crazy when my J key wasn't working like it was supposed to. Other than the console stuff, which isn't that big of a deal, the controls feel just fine.

I was really annoyed that they decided to combine several actions into one single button (default: spacebar). I changed it to left shift (although the game was still telling me I had to press spacebar instead...). So that's one button for sprinting, interacting with objects, getting into cover, etc. Maybe I missed something, or they updated it since I last played (I decided to play through the first game again to import my character), but I didn't see any options to split those actions up into separate button presses. I'm seriously considering trying xpadder. My first play through of the first game was on my 360, and I didn't have a problem with it, so I wouldn't really mind using a controller again.