Borderlands sells 2 million worldwide.

[shio]

Barozi said:

I'm pretty sure 2K use shipped sales in their financial reports.
It's christmas time, so they shipped even more copies than usual, that means the PC version has probably the same sales as the PS3 version + digital distribution sales.
Overall around 500k.

lol @ shio as usual.

 

EDIT: On a second thought...probably less than that.

If they are only counting shipped figures then the PC version is doing even better, because nowadays most sales on PC are from digital distribution.