Lets just hope that you and myself don't turn up at a game shop a few hours/days later trading it in 
That's the whole point though, mate. You MUST RESIST the urge to go trade in games that don't IMMEDIATELY 'do it' for you. Some games take time and a little effort before they gel with you. You've got to be PATIENT with some games sometimes!
Battlefield 3 will take more than a few hours or even days to get used to *if* all you're ever familiar with is manic fast action shooters like MW. If, however, hyper fast gaming is your bag then I would strongly recommend you never buy any games that don't fall into this category, you will be disappointed.
BF3 isn't as fast paced and I know you know that already but it isn't exactly glacially slow. Sometimes the action can be pretty frenetic. It's a world away from very slow strategical games, like, um, chess. The jets are fast. The tanks, pretty slow. The jeeps are nippy and everything. And sometimes, it's a real drag as there's no frickin' vehicles left at base as they've all been taken and you've gotta hike for miles on foot which sometimes results in much wasted effort as you'll get blown up just as you reach your destination. It doesn't happen all the time but, in my experience, it happens.
So, if you don't like the sound of this then don't get it. I know, anyone unfamiliar with the Battlefield way of playing, will maybe be thinking, why the hell play the game then? And the answer to that has to be found in the question of what individual players actually like about the game. I'm not going to say anymore about that aspect but the videos linked to by mrnelster recently do go quite some way in providing answers to that question so, again, if you don't like the look of sneaking up behind a tank to blow it up with C4 then this game is not going to appeal. For me, Battlefield has a fair amount of sacrifice as you'll be in situations where the odds are highly stacked against you and that's the draw - it's highly likely you'll be killed by that guy sat in a strategic position spawn killing everyone but it feels sooooo satisfying when you can get to the little fugger and blow him up. It might take you 10 attempts but it's like beating the cr@p out of him and feels good.
Anyway, too much insight into the mind of spook given here. If you get the game, don't expect a quick fix. Look at it as an investment into some truly epic moments and, hopefully, some great team/squad based gameplay (if DICE get that part right). The beta didn't impress at all on the communication front: the map was poor, there was no VOIP, the squad system sucked but hopefully these things will be fixed on release. If DICE put their money where their mouths are (and I think there's good reason to believe, for the large part, they have) then we gamers are going to be in for a treat. Roll on the next generation of gaming!
I can't wait!