It looks like the PC version of Borderlands
will be available at your retail shop as well as through Steam. No word on if they are coming to other services like Impulse yet but we'll let you know if we find out.
The folks at Destructoid have found out
that the PC version will get two additional features not found in the console versions of the game. The first is the ability to select and export your weapons to a JPG so that you can share our loot finds with friends. The second feature is a timedemo feature that will allow you to benchmark your PC with the game and then compare it with your friends or check out how much improvement that shiny new $500 video card really made in playing the game.
After playing the game
I'm starting to think that the PC version of the game is going to be the best of the three versions if only because inventory control will be much easier and Gearbox has promised slightly better visuals on the PC version of the game.