Not only is it using the Frostbite 2 engine, it is also using the "ANT" engine, the same one used in games like Fifa for the realistic movement of the soldiers.
I have been a fan of the Battlefield series since 1942 was still big. When Battlefield 2 came out, it was amazing. It had huge maps for jets and, my favorite, snipers. It was also one of the few games to have bullet drop, or have gravity effect the bullet of a sniper's round, something i really love about Bad Company 2.
I cant wait to have the destructible environments of Bad Company, and the squad/platoon/commander part of Battlefield 2. Add the mortars, ammo and vehicle drops, and UAVs, Jets, being able to go prone again, and the Frostbite 2 engine, this will probably be the best FPS ever, and stay that way until BF4.
The multiplayer will also be geared more towards teamwork than most FPS's now. In BF2, if your team didnt work together and your commander didnt do his job, you would lose. In COD, one person could win the match for the team. Even Bad Company 2 could be better for squads. In the console version barely anyone joins squads.
Anyway, sorry for my rant
. I cant wait for this game. Ive been waiting since everyone went from BF2 to COD4..