If Wayland's adoption takes off and that it indeed is being widely used by tier-one Linux desktop distributions and the future direction of Linux is clearly with Wayland over X11/X.Org, the necessary pieces will fall into place within the NVIDIA binary graphics driver for supporting Wayland. That was heard while having dinner with a certain individual last week in Germany.
Don't expect NVIDIA to go out of their way to support Wayland early or to have any surprises when Wayland 1.0 is released soon, but they're watching the space and seeing if Wayland is indeed more than just a fad. It will likely be at least a year or two before we see how Wayland plays out since Wayland 1.0 is just the starting point and it won't be until next year when Ubuntu may use Wayland in some capacity.
Should Wayland support come to the NVIDIA binary driver, you also won't find them abandoning X11 support anytime soon due to needing to support the enterprise Linux distributions. Their largely shared driver code-base also needs to be supported on FreeBSD and Solaris where there isn't any work on making Wayland compatible with non-Linux systems.
AMD Catalyst also doesn't have any immediate Wayland plans.