The wife and I saw Gravity this morning. Really very good. While it was sufficiently intense, by the comments here I was expecting it to be pretty much a nail biter nonstop, and that wasn't the case. I disagree with underEJ; I felt Cuaron did a great job of giving the audience some breathing room to chill before upping the intensity even more. And I gotta disagree with Reaper16, too. I didn't find it particularly "scary" at all; thrilling, definitely.
And I'm not a Sandra Bullock fan at all. She's generic and better than average on her good days. I've always been very touchy about the fact she has an Oscar for The Blind Side - a role in which she was perfectly fine, but not extraordinary (also worth noting the same year she got a Razzie, the first person to win both Oscar and Razzie in the same year). She was extraordinary in Gravity.