Not sure what the issue with Windows LIVE is, I don't have any problems with it myself. Anyway, thks for the answer all.
I don't know if this is the reason they went to Steam, but we did have a lot of problems with the DLC and GFWL on the release days. As far as I know, it went pretty well with Steam, but the DLC was already out there by then. We'll see how it goes with New Vegas.