I must admit, the more time goes on the more I find I'm gravitating towards small-to-mid-sized maps that allow one to be successful either on foot or in a vehicle. Too many maps, especially on Conquest, make vehicles an absolute requirement for success--and sometimes, I'd rather work towards my weapon's dogtag or next service star rather than having to hop into a tank in order to have a fighting chance. On the other hand, I find I don't enjoy maps where vehicles are completely absent. They change things up and add an element of strategy. Operation Firestorm actually works surprisingly well either on foot or in vehicles; given its size and the number of tanks and jets and helicopters, one would think that infantry on that map will only get points if they are on anti-vehicle duty. Caspian Border, on the other hand, is a little too big and open for infantry to do much more than capping flags and shooting rockets at vehicles.
Personally, I don't find myself excited by either announcement. What would really get me back into this game is if they announced a fix for all the hoops you need to jump through just to play on the same team as your friends. A competent matchmaking system that is party-friendly or lobby-friendly is what this game really needs, and it shouldn't be too hard seeing as how it's been perfected since Halo 2!