What I find interesting is that Cryptic's logo is still on the box of the Mac copies. Someone was smart in that final sales contract.
NCsoft probably licensed the engine "in perpetuity" for a nominal sum of money given that supposedly the CO engine is derived from the CoH engine so if Cryptic sold *everything* CoH-related to NCsoft they would then have to license back their own engine for CO since it's a derived work, which would suck.
If you already have CoH/CoV for the PC you can buy the Mac version and get a month of game time added to your account and get the "Mac exclusive" items (costume pieces, Mission Teleporter power), all for only $20!
The extra items are supposed to be available in a couple of months as a separate purchase but it's not likely to be any cheaper than if you just buy the Mac version (effectively only $5 not inc. tax).