Borderlands and DRM

[Jekken6]

I've been trying to find out what kind of DRM the retail copy of Borderlands for PC uses, and I'm a bit confused.

Here's what i know so far: http://gbxforums.gearboxsoftware.com/showthread.php?t=75949
I want to know if: I can register the game on Steam and play through there.
How online works
And just general stuff about what DRM it uses and how online play for the PC version works.

 

[Snotnarok]

It's on steam, I don't know about the other details but it's coming out a few days after the console versions.