I enjoyed ME2, but it wasn't an "oh my God this is awesome" kind of game for me, so I kept putting off buying ME3. Once I heard that they were releasing the trilogy, I decided to hold off until that came out. Might as well get the whole series and play through ME1 first, just so I actually know everything that's going on instead of the small comic thing that I read at the beginning of ME2.
And that, my friends, is the most uninteresting story ever.