It's hard enough keeping track of new and upcoming games on Steam, but what about games you already own, or have played, that get updates? Unless you were really keen, that was almost impossible. Until now!
Valve has added a new section to the Steam store's front page, right underneath the "Featured" section, that highlights some existing games that have received updates (patches, new levels, DLC, etc). There are three shown at any one time, but you can expand it to show a complete log.
Because it covers the entire marketplace, it's obviously going to be full of games you've never played (or even heard of), but hey, even a casual scroll told me there'd been an update to the Just Cause 2 multiplayer mod, which is nice.