Two new all-gameplay videos from Valve show a couple of tools you'll be using in Portal 2, both of which launch you through the air. Some creative use, in conjunction with the portal gun, is required. Isn't it always?
Repulsion gel (above) looks like it works like silly putty in reverse. Instead of it bouncing everywhere, it bounces you (and associated objects).
The Aerial faith plate (at bottom) is a kind of angled trampoline that can get you where you want to go, and get others where they don't want to be.
Portal 2 is coming out next year on PC, PS3, Xbox 360 and Mac, but the videos done told you that. Twice.