It APPEARS to me that they have mostly moved to Europe. Condor Club EU appears to be quite active, with several upcoming races:

http://www.condor-club.eu/comp/competitions/202/

There may be other such virtual race clubs, but this one and gliderracing.com are the only two of which I'm aware, except now the one from Brad Alston above (thanks, Brad).

Condor Club EU is a paid membership. I'm a paid member and I'm fine with that - not very expensive for what I'm getting in return (landscapes, flight tracks of great pilots, flap settings dials for various planes, etc.).