A Portal 2 trailer was shown at Sony's press conference yesterday. The reason Valve were hanging out there is because they've brought the Steam Cloud over so now your saved games on PS3 will be stored like they are on the PC with games which support the Steam Cloud ie on the Internets.

Here's the trailer and some gameplay footage that IGN captured, I must say I'm quite impressed.

Part 2 and Part 3.

Portal 2 will be released for PC, Xbox 360 and Playstation 3 next year.