I have a monitor whose native resolution is 1440x900. I have an Nvidia GeForce 8800 GT, and I use the nVidia control panel to scale anything lower with a fixed aspect ratio. That means I normally get black bars on the sides of my screen when running a game that uses a 4:3 resolution.

World of Goo, for some reason, ignores this and stretches to fill the screen. That means everything is really fat. What's going on? The pre-release demo didn't do this!

edit
Evidently there's something really strange going on with the way World of Goo starts and displays. If I alt-tab out of the program and then go back to it, it displays at the proper windowboxed and 4:3 800x600 resolution.