While I enjoy Battlefield: Bad Company 2 enormously, I also miss the  large 64-player maps of Battlefield 2. 
 
You kinda need a giant map to have jets on the thing, anyway! 
 
Here's hoping Battlefield 3 will retain the "map plays different every time" mechanic of the destructible buildings, trees, and walls of BF:BC2 while increasing the scope of the battlefield.