Oh there are glitches alright. During my first playthrough I barely noticed them - but in my second playthrough, suddenly they're all there.
The most annoying glitches are when Shepard gets stuck in the air - usually this happens as you are approaching cover at a slightly odd angle. On Jacob's Loyalty Mission, I was walking around, when suddenly I got stuck in the air above a piece of cover near a cliff. I couldn't get down - even walking off the cliff didn't kill me (I just ended up in a void). I restarted from an auto-save point - only find that the game autosaved when I was in mid-air. Had to start the mission all over again. Once again on Omega station in the clinic - tried to talk to the clinic receptionist, got stuck on the desk of the clinic and then ended up sticking out of the roof of the clinic into the scenery. Had to restart then too.
During the final mission, just before the area with the last bossfight, one of my squad members got stuck. He had frozen in place. Pressing "C" to call him back did not work. Trying to get him to use powers did not work. Hitting him with a melee attack did not work. Had to restart then too - only to find that when going through the area again, when I took cover, Shepard magically managed to launch himself 300 feet into the air, only to suddenly die.
Also, if you skip the dialog by pressing space too much, the game can have trouble properly positioning characters. This has led to some instances in which I had squad members walking in front of me during dialog scenes.
But having said all that, the glitches did not occur often for me, and I had a blast playing ME2. The glitches do not occur that often, and although they can be annoying, just reload a save. The only real problems I have had have been getting stuck in the air, but they aren't too common.