I didn't notice this during my time with the game last month, because I was either rolling along blissfully or exploding disgracefully, but EA's upcoming Battlefield 3 has magic tanks.
And they are magic, because they're capable of doing something no actual tank has ever been capable of: healing themselves. Yes, in Battlefield 3 tanks (and any other armoured vehicle for that matter) can, if "lightly damaged", take cover away from enemy fire for a while and, if they don't get hit again, recover their health. Just like the infantry can.
Developers DICE say it's "our way of giving smart non-Engineers a fighting chance to keep his vehicle in the battle", but there'll be some -- no doubt those waiting in line back at a spawn point for a tank to blow up -- who will be less enthused.
Battleblog #9: Online vehicle warfare refined [Battlefield]