Wow, you could inform yourself a little bit! Check out a LP, or download the demo (which is super handholdy). Either way...
You get 6 guys max, but the combat system has been revamped... which is to say that it's different. Less flexible, but more streamlined and thus less boring. Most people seem to like it at least as much as the previous one.
It's a different game. Less complex, less micromanagement, and perhaps a little more linear, but I'm loving it. Funny thing is, I was a huge fan of X-com but always save-scummed to never have any of my guys die. This one? It's all about ironman mode. It really DOES make you care about every single one of your troopers, and every choice, every shot REALLY counts. I am much more involved emotionally in this one than in the old X-com.
Of course, if you're a fanatic that will not take well to any changes ever, then you won't enjoy it. It IS different.
Cthulhu: HAHAHAHAHAHAHAHAHAHAHAH
Awesome! I can't wait to get home today... and download a huge patch before playing? Dang...
Also yeah, the game progresses whether you do the missions or not. I've actually found the arc thrower to be a decent WEAPON for when you go out of ammo and the other guys are almost done. Pistols might not cut it. This has actually saved a couple of my guys without me expecting it to. On the other hand, grenades wipe cover out (something I always seem to forget) and allow others to show at enemies without any cover penalties. I totally need to start doing this to the stupid squads of Mutons.
Also, did anyone notice thin men don't seem to take damage from grenades if they are in cover? The cover gets destroyed, but they're handydandy. Or did I encounter a bug in a mission?