First: movies . Now, Valve has announced that it wants to be your supplier for non-game programs. Beginning September 5th, you'll be able to grab a variety of software ranging "from creativity to productivity" that "take advantage of popular Steamworks features, such as easy installation, automatic updating, and the ability to save your work to your personal Steam Cloud space so your files may travel with you."
The press release didn't give any specific names for launch titles, but it was revealed that devs will be able to submit apps for the community's approval using Steam Greenlight, just as game creators can.
"The 40 million gamers frequenting Steam are interested in more than playing games," Vavle's Mark Richardson said. "They have told us they would like to have more of their software on Steam, so this expansion is in response to those customer requests."
As far as I know, the non-game software market lacks any sort of Steam-like unified distribution platform as of now, so this is a potentially huge development. What kinds of applications would you like to see added?