Not going to defend the ending as great, it wasn't IMO, but it is hard to believe people are so upset that they allow the last 5 mins to ruin the entire story. I loved ME3 as part of a trilogy up until the final elevator ride. The game had the most epic moments with your companions. Garrus day out, Mordin, Tali and the resolution to the Geth vs Quarian conflict. Even the conclusion to companions such as Jack, Jacob, Wrex, Miranda, Kasumi and the rest were done really nicely, just not with the same emotion as Mordin and Tali. They even tied up lose ends from the DLC from ME1, so to me the game was epic until that elevator ride. The new redone ending was more than enough to make me happy. It tells me what happened to my companions and that was all I cared about.
I have only played through ME3 twice, but that is due to another game taking all my free time, not because ME3 was a terrible game, it isn't, it is a great game with a bad ending. Just like RotJ is average movie, with a terrible ending. Ewoks...need I say more.