Please have a look at this tournament.

http://www.littlegolem.net/jsp/tournament/tournament.jsp?trnid=twixt.DEFAULT.mc.2006.final

Somehow I happened to have ended up there. Ist this the “final” tournament of the 2006 monthly cups?

I wonder if all of these top players are still playing the game…

It seems like there was a bug that prevented some tournaments from starting, and now, the problem accidentally “solved” itself. See also this similar thread. Maybe there are similar cases with other games. Maybe contacting the webmaster helps?

These tournaments have been going on for multiple games.

AFAIK, this is not a bug, but a new feature that is implemented recently without being publicly announced :) Note that the name of the Monthly Cup in the game page is changed to Cup.

I see, looking at various -monthly- cup pages, I think you're correct that these final stages are a new feature, which will be applied to all years. So twixt.DEFAULT.mc.2007.final will soon be started, when some condition I don't know is satisfied. But I think it's a bug, or at least an annoyance, that these final stages are created for all past years. In my opinion final stages should only be created for years where not all monthly cups were finished at the time of the introduction of this feature.