Time Units are dropped as each character can move and perform an action, there are classes, 16 individual countries with pros and cons, and Sectoids, Mutons, and Cyberdiscs are in.
There's a new wealth of information that's come out of the Game Informer piece on Firaxis' XCOM: Enemy Unknown. It seems missions are mostly procedurally generated.
Outside of a few story missions, the exact same mission will never repeat because of all the variables at play say Firaxis. The Game Informer piece has been pillaged for its intel on the newly announced XCOM, and NeoGAF has handily collated the information as well as from other sources.
Fog of war is featured, enemy spawns are random, a mobile platform called SHIV that's customisable, you can upgrade your base of operations, 16 countries make up the 'funding council' that need to be kept happy. Snipers can grapple to building rooftops, gunners can suppress the enemy and characters can have all manners of customisation too.
Dead characters are treated to a cinematic and if they die brutally their gear could be permanently damaged. Inexperienced agents can freak out if it all goes wrong. The PC version is said to be getting an enhanced interface with Dragon Age: Origins as a big inspiration to the team.
Environments are destructible, experience bonuses maybe withheld if squad members die, levelling up a character lets you choose from two abilities. You can't recruit classes only level up rookies and then choose their class. Firaxis call this a 'reimagining' and not a reboot for the classic PC series.
Action points are dropped as the team doesn't want people messing around working out costs, instead each member can move and perform an action. Soldiers can panic but won't kill the squad - it's to make gameplay fairer. The switch between tactical and strategic gameplay remains the core focus of the game.
Vehicles replace a squad mate in the field, but they don't gain experience and when destroyed they're gone for good. Aliens get their own perk abilities with Sectoids, Mutons and Cyberdiscs all confirmed, as well as Thin Men. For more information check out the lengthy forum post on NeoGAF.
Are you excited that Firaxis is reviving X-COM, video gamer?