londrum - 8:33 pm on Sep 22, 2011 (gmt 0)
dave_hybrid: you could just write a little script that checks whether the thread has received a reply yet, and if it hasn't then slap a noindex metatag on it.
that's what i do with my forum (phpbb). that would probably bring the number down to an acceptable level. and you wouldn't have to keep managing it.