There wasn't a great deal of love for Quake 4 back in the day. I'm not sure how much of that was gamer sourness at being forced to actually purchase the new version (considering many were able to download and play Quake 3 for free from LAN adventures), but it wasn't particularly well received among the competitive community.

It's a shame, because Quake 4 solved one of the major problems facing arena shooters at the time -- sitting in a server, waiting for your turn. At the time iD called it instancing, where you could have multiple duels ongoing within a single server, but the technology was never utilised anywhere else.

With the return of arena shooters, and more deathmatch-oriented FPS in general, I've been hoping that the concepts and tech might be revived. And it has -- in the latest Unreal Tournament.