Apparently only a couple (so far) have been offered publicly for resale. I don't know how many hundreds or thousands have processed, but off hand, I'd say that's a remarkably small number. Of course there's no way of telling how many have been resold through private (non-advertised) transactions.
The last set of numbers I saw for the one listed on Gun Broker indicated the seller was only going to clear in the neighborhood of $125-150 (after paying selling expenses, FFL, etc.). Let's say prep time of putting the CMP bid package together, mailing it, tracking, etc. of two hours; that's $60 to $75 per hour. Not that great of return on time (IMHO).... but to each their own. Hope he enjoys taking his wife or girlfriend out to dinner because he ain't likely to get another shot at CMP (assuming they make good on their threat).
If CMP's main concern is pistols getting into the wrong hands and this kind of activity bringing about an end to the program, I don't think that'll happen. Bad guys can find a lot cheaper pistols "on the street" than these. Much more likely a problem would be stolen pistols (IMHO) than this resale issue.