hmm, I conclude this with one thing: Apples and oranges may not be compared because neither is the same yet may share parts akin to the other.
I would say more, nay could write an essay upon the ups, the downs and the difference between the two, but I'll save the paper and say that nether is better, neither is worse; they are different and that is the point to be made.
Usually I'd go on the same leve as fern but i have a different opinion this time. As a very casual gamer, with broad interests in all game categories except for fantasy pony MMO, I found that as each game intrigued points the other did not, the biggest issues I have had were with MW3.
For a game that boasted dedicated servers, having to enable it in the option is certainly not an encouraging move to supporting them. BF3 is dedicated servers and although they are limited to private companies that level of customisation is still there none the less. I suppose this is from a hosting perspective. When it comes to patches, BF3 probaly has had the most issues, with buggy releases and in tihe begginning, patches that just gradually caused more crashing than the previous. But it's at a point now were it's all stable. MW3's matchmaking has definately improved from MW2, but you still can end up with the inevitable bad host, or host that disconnects mid game, which is just plain infuriating.