Normally I review games, but there's really no point with Mass Effect 3. You've already made up your mind if you're going to buy it or not, and nothing I say is going to change that. Instead, I'm just going to cover the much ballyhooed ending.
In short? I liked it.
You still want the long version? I suppose... though you might want to stop here if you haven't played to the end yet.
I started up Mass Effect 3 expecting an ending that wouldn't be a nice tidy package. I would have been disappointed if that's what Bioware tried to do. What happened surpassed my expectations in a very good way. It was bold. It was powerful. It made you think. It left questions open. This, as Penny Arcade's Tycho put it, is the school of hard sci-fi endings.
A lot of the complaints have centered around how all of Shepard's choices up to this point didn't matter. I can see why people would think that, but it doesn't make it a valid excuse. Yes, there's pretty much only one outcome for Shepard's cycle, and it generally sucks for anyone still alive when the citadel fired. I think Bioware made it pretty clear that the reapers couldn't be defeated by any conventional means from the start of the game. This is where Shepard had to be to end the threat of the reapers. Could they have done more to show the results of all your hard work? Probably. A lot got glossed over at the end.
Ultimately, it comes down to this. Bioware isn't finished with the Mass Effect universe, and it's a safe bet that future games will involve this future that Shepard created. Bioware might as well have confirmed it when they told everyone to keep their Mass Effect 3 saves around. The legend of Shepard will likely play a large role. Most people know how a legend ends, but it's the route the hero took to get there that makes up the real meat of such a story. As a wise man once said; it's the journey that matters, not the destination. All of those decisions you made will matter for whatever story there is to come.
Don't take all of this as me thinking they couldn't have improved on things, because they most definitely could have. I was seriously disappointed that they didn't use any of the great time shifting stuff they did with Dragon Age 2's story. Jumping ahead a year or two into the reaper invasion could have added some serious weight to the story. It could have also given some of the past decisions you made a chance to better manifest themselves.
I also can't help but feel that they lost some focus about half way through the story. The first 5-8 hours were tight as Shepard went from crisis to crisis trying to find stuff needed to fight the reapers while simultaneously forming alliances so the galaxy might have any hope in hell of stopping them. By hour 10-15, I realized I was buying fish in the citadel presidium commons while Anderson was back on earth in some rubble-filled hole trying to just stay alive. A more linear approach to this final part of the story might have been in order.
I should probably end this rant before it gets too unwieldy. Did I like the ending? Absolutely. It had real weight. No "happy ending" would be able to carry that same weight. Sure it could have been better, but not significantly so. It made me excited about the future of the Mass Effect universe. Nobody has ever really tried an epic in video games, and that's what this is shaping up to be. Games like Mass Effect, Bioshock, Half-Life, and others give me hope that games will continue to evolve the medium of interactive storytelling. Or we could just, you know, settle for the next Call of Duty release.