People who complain about the ending don't know what they're talking about. The story was wrapped up and the solution was made. It may not have been exactly what was expected but the knot was indeed tied. There were some unanswered side plots (i.e. krogan species future under the leadership of Wrex or Wreav) but other than that, the game ended great. I've replayed the entire series many times to gain multiple experiences in the storyline and I've always had a blast and grown to love the characters. I've never been so, for lack of a better word, emotionally involved in a storyline such as the one in ME series
I gave it 10 rating but I do have a huge problem with the way EA tried to make extra money by only allowing good ending if you play multiplayer (and pay money) or play iPhone/iPad game (apple money). Really, shame on you EA. Fortunately there are ways to get your galactic readiness level to 100% without the need for neither - just search around the bay.
If you have a high final score, the ending is awesome as is the game itself. It stinks that the paragon/renegade means nothing at the end, but oh well.