This is a great game, until you get to the ending.  Bioware has said many times that this was going to be the final episode in the travels of Shepard.  So one would expect an epic ending of an epic series.  Instead you got what I would say is a rushed ending, that didn't answer any of the questions so many of us had at the end. 

Something completely different from the previous 2 games ending's.  You felt like you actually had something to do with how the game ended in both ME1&2.  ME3 I think failed on delivering the epic ending we all were promised/expected.  Bioware is a great gaming company and while I am disappointed in the ending of the game.  I'll keep supporting the company and buy their games. 

If this was the first game in the trilogy that you played you would probably be happy.

The multiplayer aspect of the game is also quite fun and brings something new to the series, alot of people didn't like that your single player game was affected by the multiplayer portion of the game.  I had 4 other friends who also bought ME3 so we all just played together.  (who I might mention also were disappointed in the ending)