Okay. I've beaten the game and got to the ending. And my general opinion of it is that
it's not much of an ending at all. None of the plot points in the previous games make any relevance whatsoever, you don't see any Asari, Krogans, Turians, Quarians. What's worse, you had that stupid kid that LIES because he says only one option causes the Mass Relays to be destroyed... but all the options do that. Stupid damned kid.
One other thing, why was Joker flying away? It makes no sense at all. And now all the alien races are stuck on Earth which has been destroyed. Facepalm moment.
I still love the game. I can't really start hating something due to the final 20 minutes of the game. Bioware reacts to comments so hopefully this issue will be resolved somehow, either by retcon, DLC or other solution. Love multiplayer too. It's really addictive and makes sense for the story.
Here's an alternative ending to give you all the happy feeling you deserve.