Originally Posted by
Queue
Well, you wouldn't use their Steam username, that'd be absurd (never ask a user for their name/password for another service). Steam supports OpenID to let third-parties have Steam authenticate users for them. The point wouldn't be security regardless; it would just make logging in trivial for the end user since they wouldn't have to remember a name/password. They have their preferred name set in the VaultMP launcher, and then simply connect to any given New Vegas server and their character data is retrieved based on their Steam ID rather then them having to enter a name/password.
Fallout 3 users would have to manually enter a name/password. I'm aware Fallout 3 is also available on Steam, but am not sure how integrated it actually is with Steam (whereas New Vegas is only available via Steam).
Queue