Plenty of players will leave classic and continue to do so. I doubt very much that many of them will go to retail and stay though.
I think its safe to say that Classic will find its ‘crowd’ and maintain a healthy population for some time yet. The key question is what Blizzard will do with Classic, TBC and WOTLK over the coming years because if Classic launch has shown anything it is that there is still huge interest in the older versions of the game, at least the first three anyway.
