Why are you people worry about it so much? Contax to gone but Leaf and Phase One still makes backs for it. Mamiya has been around for a long time and there are a lots of 645 AFD cameras around, just look at ebay. I got three AFD for my P45, one for auto lens, one for manual lens and one spare. Don't worry, just shoot.
What I'm trying to say is that rental outfits and bigger catalog shooting studios, who are the mainstay of the business aren't going to buy used cameras - hunting for spares on ebay is not their business model. they will "automatically" migrate to Hasselblad now, which means a diminishing marketshare for Phase and Leaf.
A diminishinng role for Phase and Leaf is not good for us.
The rest of us will be free to pick up the crumbs on the pre-owned market - I will certainly buy a used MF camera and back in a year or two.
And, just a thought - now that independent backs will be targeted at defunct systems, maybe someone will now finally come out and do the unthinkable - make decent cheap backs for the zillions of Hasselblad V's out there !