I am new to Battlefield, and have played every COD game out. Will get MW3 as well, but this game is amazing on its own!
I won't talk too much about the campain too much because it wasn't all that great to be honest. I will say this though that it's not as bad as some people are making it out to be, and I don't know if that's because there are COD fanboys trying to bash this game, but that's just childish. It is still a solid campaign compared to other crappy games, and deserves at least one play through. The frostbite 2 engine still shines, especially if you have an awesome PC that can handle the extreme graphics set by Frostbite 2's engine. I haven't played this on the PS3 or Xbox360 yet so can't comment on the console versions.
The multiplayer I would say is not for everyone. And what I mean about that is people without patience should not play it if they are not willing to give it some time to learn the basics. I hate to bring up COD in this review, but I will compare it in a generic way. COD maps are much smaller, fast paced, and no vehicles and other things to learn. You have your team and you shoot the other players, capture flags, etc. etc. With Battlefield, you have massive maps, a lot slower (but not less fun) type of warfare, vehicles that you need to adjust to, and some of the same objectives as COD.
The thing that is the most frustrating about multiplayer in BF3 is that the maps are huge, and sometimes you get respawned so far back to your base, and it takes a while to get back into action. I guess that's also good, so you don't get killed right away for respawning next to your buddy, but it sucks to have to run back to the battle when there is no vehicle next to you.
All in all, the graphics are amazing and do deliver, the story is okay and should be played through once, multiplayer is an amazing experience (and different than COD, which is a good thing because we have a different type of shooter to look forward to), and this is well worth the money and should last you a long time. Pick it up and enjoy the battle!!!