Found these previews from someone from the official forums:
"Some points I haven't seen mentioned yet here, thanks to GetWellGamers on SA:
- There's an inventory, and they said you had to manage it with items having relative sizes, which is cool.
- One of the loading tips talked about "Stop!worms", which is apparently a consumable that would let you essentially pause the countermeasure timer when hacking.
- You can eavesdrop on or initiate conversations to get side-quests, which you'll have a logbook/journal to keep track of.
- Dialogue menus are presented in general terms a la Mass Effect, but when you highlight the response it previews the entire response, which I really like. I hated having to guess the specifics of what I'm about to say.
- I didn't get any sort of "mini-game" vibe from the dialogue, not even any real time limit like Mass Effect or Alpha Protocol. They just hung out 'till you answered.
- You can drag bodies away to hide them. Minor, but I always liked doing it in DX. Also enjoyed tossing them into things/places that would gib them- hopefully the trend continues.
- Looking around corners/cover looked really great. You can really see a good bit down the way from where you're peeping into without exposing yourself. Again, minor, but it's one of those things that always bug me.
- Vent-crawling is still a staple of infiltration, which for those of us fond of ghost runs is a welcome addition.
- People react if you're walking around with your gun unholstered. Civvies will put their hands up or flee.
- Lots of classic augs- see through walls, cloaking, strength augs, jumping augs... They were playing on infinite Bioelectric and infinite health, though, so who knows.
- Lethal and non-lethal stealth takedowns, but disappointingly: "You can go through the whole game without killing anyone except the boss characters"
- Apparently the weapon mods are still in, though they were cagey as to whether they'd stack like the accuracy, reload, etc. mods from the first one.
And from ImpAtom's impressions, also on SA:
- Codes can be entered manually, but if you have the code, it pops up on the side of the screen.
- The crate carrying animation is literally identical to Deus Ex's, see-through crate and all.
- There seemed to be multiple paths through the levels, but we'll see how that actually pans out.
- NPCs talked and gave you hints about stuff without having to talk to them. In general, it seemed pretty good to me. I did think the dialogue sequence they showed off could have used more interaction, but I'll survive.
- You change outfits if you're going to be dropped off in a combat area, but you can still fight in the trenchcoat and such in public areas. The coat is just to hide your cybernetics/mechanical parts better. You basically put on something besides sensible combat gear when you're in public areas and put on something logical when you know you're going into combat. They told me that you don't suddenly change when you get into a fight or something.
- In the demo I saw, the guy got pretty badly injured. It looks like a fairly standard health regeneration system, so if that gives you hives, I don't think there is much you can do.
- I didn't like the takedown animations in the slightest, which was probably my overall largest complaint about the demo. The cover system felt weird, but that was more my preconceptions about Deus Ex then actual flaws with the system, at least from the demo.
- Everything else looked... well, basically pretty Deus Exy. I don't think it's going to win over the people who complaint that (x)
and (z) just isn't Deus Ex because it's different, but it seemed to be doing a lot more right then it did wrong. I thought the bomb-explosion aug looked pretty damn ridiculous though, and not really in a good way."