We've had a forum for over 5 years
Slot Zero set up Rune Central forums back in the days when forums were not easy to setup.
As a result, the RQ players communicate, know where to check in, and get help considering Quake has a lot of different kinds of problems. I know at Singed, it seems like I help at least 6 players a month with some sort of game threatening problem. So, we can still have hundreds of players a week.
Plus Slot Zero and Diazoild both have their site addresses as a non-participating QShmack player aka RuneQuake.com and Singed.Net so there is a near 100% awareness of the forums.
It's not because Quake is old, there is a Doom II forum with 25000 posts in just a single sub forum. It is because Quake 1 lacks a mega-site dedicated solely to the game. I've read some of the most terrible clueless advice in the PlanetQuake forums, for example.
RuneQuake isn't still going strong by luck
The community is highly organized.
And, while this probably doesn't count, by there is also a very strong Quake single player community because they are also highly organized as well. (SDA, the mappers, etc.)
And of course, Quakeworld -- which is still going strong, although struggling to deal with what is effectively a "Quake suicide attempt" where the all-important Quakeworld.nu went down and with it like 10 critically important sites and it's been down for several months now.
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