Gravity is visually stunning and believable, dramatic, and I like the characters. If you can enjoy 3-D, this is a movie that really benefits from being seen of the big screen in 3-D. As I write this, it's being pushed aside by newer releases, so if you haven't seen it and think you might like it, see it soon.
A few non-spoiler observations. It's set in the near future: there's a substantial Chinese space station in orbit. That puts it around 2020, based on China's current plans.
But it isn't our future. In the movie timeline, Space Shuttles are still operational. The Shuttle mission at the beginning of the movie is STS-157: in our timeline the last was STS-135 in 2011. And there never was an operational orbiter called Explorer.
So if you're the kind of spaceflight geek that knows how hard it is to get from our Hubble to our ISS because of their different orbital inclinations, remember that this an alternative future. So maybe sometime between 2013 and 2020 there was a mission to change Hubble's orbital inclination to match that of ISS using an unmanned spacecraft with solar electric propulsion. Such missions have been proposed in our timeline.
I would have enjoyed hearing:
Stone: Look: behind and below: ISS.
Kowalski: Beautiful. Glad they completed the Hubble Inclination Change Mission. It's good to have options.
Bullock's astronaut makes it to an abandoned ISS with a damaged Soyuz spacecraft still docked, incapable of reentry but otherwise usable if she can get it loose. How can this be? Easy. When disaster struck, the ISS had a crew of six, and two Soyuz to provide emergency escape. Fortunately, there was a Dragon cargo spacecraft docked at the time which escaped damage. Three of the crew rode down on one Soyuz, and the other three took the Dragon. It has proved that it can survive reentry four times by 2013 in our timeline, and by the time of the movie it could have been even more proven. Even if not yet certified for human passengers, it beats a Soyuz without usable parachutes or waiting in terror on ISS for the next debris strike.
For dramatic reasons the Kessler Syndrome of cascading collisions spreads far too quickly, affects too many altitudes simultaneously, and hits far too frequently.