@Robert Gentel,
Because, frankly, it doesn't "feel" like a community anymore. It feels like the PF community was assimilated by this large network of discussions. The focus of a2k is no longer philosophy, but includes such topics as "television", "food and drink", "relationship help"....
The thing is, we had already made our community at the old site, and it was a pretty good one. Then to have this happen with no warning or discussion...well...that had nothing to do with a community. It was just part of someone's plan to buy up successful, special-interest forums and then dump them into this huge forum, without regard for the members' feelings on the change. As for security issues, there are hundreds of perfectly secure vBulletin boards out there that aren't getting hacked, so I don't buy that as the main reason for this move. It was what you intended to do all along, that much is clear.