Registration for GDC 2015 just opened earlier this month, and already we've got a handful of great sessions lined up for the show that developers won't want to miss. If you have even a passing interest in the PC game market you may recall that Ars Technica senior gaming editor Kyle Orland published an interesting report about the most popular games on Steam earlier this year. He wrote it using reams of data culled from Ars' "Steam Gauge" project, which used PHP/MySQL code to trawl through thousands of public Steam Community profiles and sample data. It's one of the most ambitious independent Steam data-mining projects ever attempted. Now Orland is coming to GDC 2015 in March to share what he's learned, and run down what it tells us about the state of today's PC games market. During Orland's talk, "Analyzing the Steam Marketplace Using Publicly Derived Sales Estimates," he'll also correlate the data against market factors like Steam sales, Metacritic rankings, and much more in an effort to make the business of selling games on Steam a bit more transparent. You'll find it on the Business, Marketing & Management track of talks, and it should hold learnings for all game industry professionals. In the months ahead, conference organizers look forward to announcing many more GDC 2015 sessions. In the meantime, don't miss your chance to save money by registering early -- the deadline to register for passes at a discounted rate is January 21, 2015. GDC 2015 itself will take place March 2-6 at the Moscone Center in San Francisco. For more information on GDC 2015, visit the show's official website, or subscribe to regular updates via Facebook, Twitter, or RSS. Gamasutra and GDC are sibling organizations under parent UBM Tech.