It has a few issues, but play it for the absolutely incredible story. You won't be disappointed.
Plus:
- Great storyline
- Excellent game play
- Great variety of characters; make sure you play each one's mission to gain their loyalty as they relate to the main story line. I found Mordin to be a unique and humorous addition.
- Visually pleasing cinematic cut scenes.
- Excellent replay value as you can change your character to be soldier or biotic or vanguard,etc.
- You can take your ME1 character into ME2; nice option!
- Voice acting other than male Shepard is really good.
Minus:
- The male commander Shepard voice acting improved a little but not much.
- Dialog choices are not as varied as I would like. I found myself hoping for an option that wasn't available.
- Mining planets is tedious. It's a necessary component if you hope to survive the last mission by upgrading the Normandy.
- What happen to the Mako from ME1?
- I'd like to see more variety in the weapons.
Overall, I HIGHLY recommend ME2. It's a must if you enjoyed ME1.