Portal 2 once had a few of these irregularities, but thanks to a patch launched this past weekend on Steam, it's now running with unprecedented smoothness. Well, okay, it still wants to kill and insult you, but at least it won't crash when you Alt-Tab out anymore.
There's a few other changes in there too, including expanded joystick support and a bunch of localization improvements. Also, is it just us, or is that blue portal just a little bit bluer? We don't see it in the full list of updates (posted after the jump), but we just feel it.