The thing is about IGN, watch all their videos carefully... and you might notice that they have a really annoying tendency to compare everything to CoD. Even games like James Bond were compared to it and it was in no way similar to it beside shooting... To them CoD is the epitome of FPS and it does get on your nerves when they seem to rate games rather biasly.
So yeah, I am not surprised. Also, MW3 I think was...very rushed... compared to many other games that were coming out this seemed to be coming out quicker than usual and not much of a noticeable change is seen. Eg. Graphics looking exactly the same, only small changes like a new mortar/sniper thing and a reflex sight changer. I like both BF3 and MW3 series of games because I'm fairly adaptable in my playstyle, I want to play a game that provides a new experience. BF3 is looking really good atm with graphics (Yes, yes I know... graphics dont make a game perfect, eg. Goldeneye, Banjo Kazooie, Zelda, Rayman) and mechanics but MW3 doesn't look like it really changed much, and I don't want to play something that seems to have the "I've done this before" now feeling, unless they are aiming to do that.
Also, what I don't like about CoD is how they depict war.In the BF and MoH series, there is a feeling that these are like real people, they have families etc. In the new MoH, despite the somewhat bad sales release had a incredibly good ending. In CoD they tend to glorify war, and believe me I have seen loads of YouTube comments about people wanting to join the army cause they assume the know everything about army protocol and weapons from CoD - perhaps the reason why people hate the fanboys are because of this.
In addition perhaps, is the fact that because of the crappy releases (according to people) of CoD recently, is that all the gamers are going to transition along to BF3 with the same mindset and playstyle in CoD that doesn't work in BF with lone-wolfing - that's a possibility.