It's going to be a big day on Monday for fans of Valve's Steam digital distribution platform, especially if you're the kind of gamer who's as addicted to the couch as you are your games.

That's because Valve will allegedly be launching its first public beta test of its new "big picture" mode for Steam, a transformation that's designed to widen the service's accessibility beyond a conventional keyboard, mouse, and monitor setup.

Big picture mode, as described by Valve, is designed to deliver, "simple, easy-to-read navigation designed specifically for TV. With full controller support, big-picture mode will let gamers kick back and enjoy their favorite games on the biggest screen in the house."

"Steam's big-picture mode doesn't require any additional development from you," reads a developer-themed description on Valve's Steamworks page. "Just ensure your game works well with a controller, and we'll take care of the rest. And don't worry, keyboard and mouse aren't going anywhereusers will be able to switch between input devices at any time."

The rumored release of the big-picture mode's beta first surfaced as the briefest of tidbits within a larger New York Times article about Valve's work culture. However, the news has also been semi-corroborated by GameTrailers' mid-August interview with Valve's Greg Coomer. In it, Croomer describes big picture mode as the following:

"In early September you'll be able to hop into a beta, click a button, and see Steam reformatted for your TV and usable with a PC game controller, or a mouse and keyboard if you wanna play that way," said Croomer, as reported by Polygon's Samit Sarkar.

While Valve's been on a wearable computing kick as of late  as the New York Times article highlights  some have also looked at Valve's big-picture mode as a sign that the company might be slowly starting to dip its toe into the world of gaming consoles as well. Similar rumors of a "Steam Box" gaming console flared up in March of this year, but were quickly shot down by Valve.

It's more likely that Valve's looking to widen the Steam experience as much as possible: From the upcoming introduction of non-gaming apps into the mix, to Steam's big-picture mode, to Linux support, Valve appears to want to make Steam a working destination for software distribution that covers every potential way that users would want to use the service.

And the recent statements about Windows 8 by Valve cofounder Gabe Newell specifically, the way in which he feels Microsoft will control the digital app ecosystem  give Valve all the inspiration it needs for pushing and perfecting its software platform above all else.

For more tech tidbits from David Murphy, follow him on Facebook or Twitter (@thedavidmurphy).