If two users simultaneously edit the same file, one of them "loses" and shows up as a Conflicted copy.
From my perspective, that seems like a good feature to consider adding. Groups of artists are used to self-organizing so they don't end up conflicting in this way, but I think that's only because they haven't had tools to solve the problem for them. We're rolling Perforce out enterprise-wide, and trying to convince artists to start storing their working files in it (PSDs, etc) -- one of the big selling points is that you can easily see that someone else is working on this file before you jump in.
From my perspective, that seems like a good feature to consider adding. Groups of artists are used to self-organizing so they don't end up conflicting in this way, but I think that's only because they haven't had tools to solve the problem for them. We're rolling Perforce out enterprise-wide, and trying to convince artists to start storing their working files in it (PSDs, etc) -- one of the big selling points is that you can easily see that someone else is working on this file before you jump in.