I'd suggest you wait at least until April, seeing as they've promised to revise/expand upon/clarify the utterly abysmal ending. The game, in and of itself, is fun. Sadly, it has more in common with ME2 than ME1, but it's playable and entertaining nonetheless. The writing, on the other hand, has taken a dive alongside the VA performance by some of the cast. Cutscenes are poorly edited and the seams are clearly showing, which can break the immersion somewhat. The story development and the gameplay structure is bite-sized, with short missions involving a contrived enemy wave-summon mechanic in the form of activating a console or disabling an AA gun emplacement etc. It features a single hub populated by dull NPCs whose conversations you're supposed to overhear in order to start simple fetch-quests which get quite boring once you note down the pattern in which they're presented.
All in all, it's a good game (the worst of the trilogy, though) but I'd wait for the revised ending if I were you... either that or simply shut down your console/PC once you hear Anderson utter the words "You did good, child" and imagine that the game ended right at that moment (it's fitting and that way you get to avoid the worst deus ex machina ever employed in fiction).