Before I answer, Colonel and Smiley, why were you guys disappointed with Eden being a computer? I think that was one of the smartest moves Bethesda did with Fallout 3. A lot of people thought he'd be a man, but instead it's a ZAX supercomputer that's even keeping his identity from his men except for his highest command.
The computer brings in the whole concept of it being infallible as it's not weakened by human emotions, but being made by man it is already a fallible machine. It was very much like Fallout 1 though, but then again I think that was kind of intentional seeing as Fallout 3 was essentially a retcon of the series (take a look at "addition" in http://en.wikipedia.org/wiki/Retroactive_continuity of Wikipedia to better understand what I mean. FO3 wasn't exactly adding in missing details [that much] like most addition-retcons, but it is essentially adding to the series but through a new medium; Action RPG instead of turn-based RPG).
Now then to answer the OP question, what I want to see at Quakecon is less action and to get more information on traits, perks, new skills/reformatted skills, a look at hardcoe mode in action, and some more information on settlements (both ones already known and ones not yet released).
But it'll probably just be a lot more of the combat system at work. Hopefully a little bit of that background stuff I mentioned too though.