They only say that they are ceasing further development, but they don't say that they are ending support for existing Aperture users, not yet anyway. I sent a query into Apple support asking if they intend to continue supporting new RAW formats. I haven't had an answer yet but it hasn't been that long and they're probably swamped.
I don't normally buy newly released cameras but I bought an Oly E-M10 and there's no RAW support for it yet in Aperture. I understand corporate secrecy, but it seems to me that they should at least state whether they plan to extend RAW support to existing Aperture users for new cameras. I guess they're worried that if they come out and say they won't that lots of pros and serious amateurs will buy something else, but by not saying anything, they only manage to annoy those very same people and encourage them to move away from Apple anyway. If they're decided their future is tablet consumer amateur use only, fine, that's their prerogative, they don't owe me anything, but it would be decent to let me know. If they don't, I will assume the worst.
Funny how the web has tended to favour monopoly (or near monopoly) instead of making more variety available. As these threads show, the only alternative seems to be Lightroom, which at least for v. 5 is still available for purchase, not rental. No one knows how long that will last, especially after Aperture is gone as a viable choice.