Completely get where your coming from. My brother won't stop raving about how amazing it is and so much better than MW2.
And yes, its the next in line from MW2, so it would obviously have some similarities. But it all feels a bit too similar to me. Like look at MW then MW2. It feels like the next installment, but completely different. And then MW2 to MW3.
Never got majorly into the COD series, but I did play on the regular solely because all my mates did. Maybe I'm missing something, and it's just not my cup of tea.