Just played the demo and got a lot of mixed feelings...
The good:
(1) Graphics: Shiny and new. Looks good, but not only that it is also...
(2) Immersive: The whole artistics style grasped me. Sound, unit animation, it all seems to work well together. Action camera is nicely done (and can be deactivated when you don't want it).
(3) Soldier classes: The class system seems like a good idea to empathize different roles for your soldiers (more like in the original X-COM/UFO, at least).
(4) The base menu: I really like the idea of a vertical base. The 3D side view is really, really cool.
(5) Locations: Being from Germany, I really liked that they actually cared to use fitting graphics for a german level. Correct cars (and semi-correct licence plates), posters (although with some hilarious denglish - no german would say "Wir hatten Spaß, nicht?"

) and building style really made me feel like being there. A job well done.
The bad:
(I) Controls and UI: Good lord, that control scheme, scroll behavious and UI is horrible. Feels completely...
(II) Conosole-ish: This seems to be (yet) another game that has to work on consoles and thus can't take advantage of PC abilites. And from what I saw, it is not only control, but also other things like...
(III) Gameplay: Compared to the old X-COM, the demo sort of confirmed my fear that the game will be "dumbed down". One example: Soldier loadout and inventory. Have you taken a look at the soldiers in the base? All weapons that are shown there are class specific. No shotgun for Mr. Heavy. No LMG for Mrs. Medic. No choise for your other equipment (granted, that will change as research progresses, but why not at least add a few different basic weapons? Where are my proximity mines, fire granates, shokcing sticks or flares?) I hope that I am wrong, but looking at CIV5 or the "new" Railroads, I will expect that from Fireaxis. The worst part is...
(IV) Map combat: The combat I have done in the demo doesn't feel like X-COM, it feels like Final Fantasy Tactics. The map is just a 2D chessboard filled with shiny 3D graphics. Even in the old UFO, the shape and size of objects was important for your fire arc and hit chance.
Why do I have to shoot directly at the aliens with regular firearms? Were is my area fire option? Why can't I "blind-fire"? Why do my granades have perfect accuracy? Why are there no different hit zones (arm, legs, torso?) Why isn't cover calculated for different vantage points? That alien on ground lower level can hit my guy who is completely concealed behind the air duct on that roof because the object only grants partial cover?!
Considering that tactical combat is a HUGE part of the X-COM series, this is really a let-down...
My Conclusion?
Seems like a game that chooses style over substance. Nice immersion, but really lacking in tactical combat (or even gameplay). Lots of sacrifices to work on consoles and appear to a wider audience. I hope that I have only seen a small part of the equipment and options, because otherwise I seriously doubt the replayabilty and long-lasting factors. (Let me tell you, I still play the old X-COM from time to time).
Really not the game I was looking for. I will wait for the reviews and keep my hopes up that the levelling system works to make tactical combat more interesting, but as it now, this game is by no means a "must have" title.
Does anybody know Silent Storm? Now THAT would have been the sort of game engine I would love to see for a new X-COM.
Learning-by-doing skill system, tons of cool weapons, destroyable enviroment, game physics, inventory, special skills and talents, different classes, good graphics, turn based combat and real time out-of-combat on-map gameplay, different hit zones...
OH GOD, PLEASE MAKE A SILENT STORM/X-COM CROSSOVER!!