Earlier this week, Valve's digital distribution platform Steam gathered 5 million concurrent users, a new record for the popular online service. Today, Valve announced additional milestone statistics concerning Steam, led by user base growth to 40 million users, up from 35 million.
Valve parsed other Steam data, too, including mention that in 2011, Steam's library ballooned to more than 1,800 games. In terms of sales, Valve said that for the seventh straight year, the service saw a year-over-year unit sales increase of over 100 percent. Additionally, Valve said 14.5 million copies of Steamworks-enabled games were registered in 2011, up 67 percent from 2010's figure.
In terms of content delivered to gamers, Valve said it served in excess of 780 petabytes (1 petabyte equals 1,000 terabytes) of data to players across the globe, which is double what the company delivered in 2010.
A new Steam service introduced this past year was Steam Trading, a system that allows users to exchange in-game items and gifted titles between themselves. And according to Valve's data, some 19 million items have been exchanged since the program rolled out in August.
Looking ahead to 2012, Valve said it is currently preparing to release the Big Picture user interface mode, first spoken of at the 2011 Game Developers Conference last February. This new mode lets gamers access Steam through their home televisions with controller support and "navigation support designed for television interaction." No release window was announced for Big Picture mode.