I played Portal 2 last week, and absolutely LOVED it. I’m dying to play it again. I thought Valve did a great job with the story, especially with the backstory of Aperture Science. The writing was fantastic—GLADoS was back and meaner than ever, but in her own hilarious way, of course. The gameplay was great, too; I liked the lasers (sorry, the “discouragement beams”) more than the pellets from the first game, and the hard light bridges were awesome.
Overall, I thought Portal 2 was a good companion to the first game. My only complaint is that you can’t play individual test chambers—you have to pick a “chapter” of the game (there are 10) and play through all the test chambers to get to the one you want. That doesn’t lend itself to the same kind of quick, repeat gameplay of the first one. (I often replay the Companion Cube and Turret levels from Portal when I’m bored with whatever else I’ve been working on and want a nice puzzle game.)
Anyways, I loved the part of the game that’s included in that video. Minor spoilers (?) for Portal 2, but nothing… too integral to the story.