The last piece to one of the greatest trilogies in gaming
Mass Effect 3 continues the story arc from the first two games, you're all in to what could be the last war of your cycle. The game keeps improving on the gameplay feel from the previous games, while changing some aspects of customization to equipment and upgrades. The experience from player to player will vary depending on what happened on your playthrough of the second game. I saw alot of people complaining of the amount of "coincidence" meet ups that the game presents. But in my case, not that many people are alive to feel like something too forced, my crew is not as big. So it really gave the sense of making decisions while being at war.
They got rid of the loyality missions from the second game, that were one of the coolest things to do. But the story telling through the missions in this one felt great, the revelations and dialogues with the other commanders where the high point of the game for me, and the famouse bad ending is actually fine, I don't really have a problem with it.
The series always had some of the best side characters you can find in a video game, and that's still a very good positive, with some new and surprising ones to find. I think this one had the best combat of the series so far, having the same gameplay but more fluid. Giving you some options based on the weight you carry to use more or less of your spells, what I enjoyed. They also got rid of you needing to go from planet to planet to scan them looking for supplies, it's one less side thing you can do but it's one less thing that you have to do, I'm kind of neutral on that.
I was really impressed by the sense of war that the game gave you, with some really amazing cinematics, specially at the end. If you liked ME2 there's no reason not to enjoy this game, I really think it gets a bad rep, they're on the same level. I give a slight edge to ME2 just because it came out first and introduced some of the best characters in the series, while is just a continuation of what you did there, but with some really cool discoveries.