With the 7 you can drag a window to the side of the screen and it snaps there and maximizes to half of the screen width.
Dragging to the top maximizes a window.
Unless I was the laughing stock of XP's UI design team, I always had to clear all the other windows as the 'tile vertically' would tile all open windows to small slices. Now I can throw Lightroom on the other side of the screen and easily swap between browser window, Photoshop, etc. on the other side while keeping lots of other windows open in the background.