Kotaku has a hands-on preview of the Steam Big Picture Mode, which will launch as a beta today. They discuss what this first step will and will not mean to PC and console gaming, and offer Valve's thoughts on how this may or may not lead to development of a dedicated Steam set-top box. Here's what they say to expect: "Here are the basics: this afternoon, when Big Picture goes live, you'll be able to push a button and turn Steam into an entirely new interface. It sort of looks like the dashboard on an Xbox 360, minus the advertisements and other clutter that can make that system so irritating to navigate. And it allows you to do almost everything you can do on vanilla Steam: you can buy games, browse the web, and even chat with your friends using the platform's standard in-game overlay." They also have this trailer showing what the new mode looks like.