Beloved developer Valve has released lifetime retail sales figures for some of its more popular games, including the Half-Life and Counter-Strike series, revealing that the studio has sold over 32.8 million games since the 1998 release of the first Half-Life.

Sales from Valve's digital distribution client are not factored in, with the figures only accounting for worldwide retail sales. With Half-Life 2, Valve began simultaneously releasing all of its PC games at retail and via Steam. The numbers were originally printed in the November issue of Game Informer, then republished by Gamasutra.

Furthermore, it was not specified if the figures of multiplatform games--Half-Life, Half-Life 2, The Orange Box--included both PC and console sales, or just PC.

• Half-Life (Valve) / 1998 - 9.3 Million
• Half-Life: Opposing Force (PC, Gearbox) / 1999 - 1.1 Million
• Half-Life: Blue Shift (PC, Gearbox) / 2001 - 800,000
  
  
• Counter-Strike (PC, Valve) / 2000 - 4.2 Million
• Counter-Strike: Condition Zero (PC, Valve) / 2004 - 2.9 Million... Read more

Half-Life 2: Episode One has obviously been released, and if you're still on the fence about whether you want to pick it up, check out Shack's full review of Valve's latest effort. Here's the short version, though: Buy this game.

Update: We now have a new screenshot gallery for Episode One featuring high-resolution shots taken directly from the game.

All in all, Half-Life 2: Episode One doesn't offer a revolutionary experience over its predecessor. What it does offer is significant improvements in just about every meaningful area of gameplay: pacing, variety of puzzles, overall density, and so on. It's a much shorter experience, but it is by no means like five hours taken out of a larger game. No, this is a larger game compressed into a five hour block. That in itself is something of an achievement; it really is absolutely packed with action to a degree that you simply never see in games that take twenty hours to complete, because that kind of development would be impractical. It makes up for the fact that a lot of assets have been reused, if touched up, and the weapon selection is identical to that of the previous game. You'll be doing so many new things in those environments, and you'll be in so many different situations with those weapons, and it's packed so full that you won't feel short changed.