I'm a big fan of Arcan (moreso than I am of Wayland), but it's nowhere near as far along as Wayland and I think at this point is still the product of just one person. I think it's fair to call Wayland viable, but I don't think I would say that of Arcan until it's:

a) generally usable as a daily driver; and

b) maintained by enough people that there isn't a single point of failure.

Right now I'm still on X.

Cool, Arcan looks a lot more viable for me than wayland