Consider that again. May 31 and July 12 saw two OINP draws. Around 2700 invitations were issued. Now lets say that about 2000 were converted into actual nominations. OINP processing time varies from 2-4 months. It is very likely that the major chunk of those were issued nomination only recently, or at least updated their profiles with 600 points recently, since the build up in 600+ category in the draws since July was never quite as much as expected, given the PNPs. Now add to this AINP and SINP nomination.
Besides, 460+ candidates cannot be as high as I said. They don't rain out of nowhere. Not like they were kids coming out from their classes in recess time lol.
I mean, come on. You seem like a logical person, and all you got is gut feeling as evidence?
As for activity for PNP guys, try following Facebook forums. They are coming around in huge numbers!!