Honestly, I liked Mass Effect 3's multiplayer mode. Oh sure, I think tying it into the war assets was a bad idea (at least to the extent that they did: 50% effectiveness by default), but the mode's fun. Blasting all those geth, rolling around as a volus, charging at the enemy and then running away like a coward. And occasionally the rare thrill (well, rare for me) of actually helping the team do something.
A lot of people are having kneejerk reactions to the idea. I don't know whether there will be multiplayer, and I honestly can't be that arsed to check, but it's not a terrible thing by default. Because, if done correctly, then it can just be ignored. Multiplayer's not your thing? Cool. But for those who do like it, or perhaps want to play with a friend, they can do it and heavily increase replayability for the game.
There's an issue of moving resources that could be used on singleplayer to the multiplayer mode, but that's not as big a deal as I've heard some people complain. IIRC, ME3's mode was developed by a team outside of the main SP guys. For instance, yes, ME3 could use some improvements, but if MP was removed it's probably be just as bad in those areas anyway.