Join Date: Jan 2008
Location: Beaverton, OR
Bikes: 2013 Kona Jake, 2015 Kona Jake the Snake, 2008 Kona Major Jake, 2013 Kona Jake the Snake, 2006 Kona Kula, 2012 Ridley Excalibur, 2008 Surly Long Haul Trucker, 2001 LeMond Buenos Aires, 1984 Pinarello Gran Turismo, 1982 Trek 614, 1979 Austro-Daimler
If you've got the tabs, you may as well go for it now. You can always upgrade again if companies come through with amazing stuff next year. My guess is they won't.
Disc hubs are pretty mature technology, though all of the good ones obviously have MTB spacing in rear. You could always put a disc brake in front, using a nice MTB hub, and keep cantis on the rear. Disc forks for racing seem to be uncommon but available. If your fork is ready, that's not an issue. The UCI decision does make the advent of hydraulic STI's much more likely, but I expect we'll see at least one season of pros using prototypes before they become available to the rest of us.
FWIW, I just put a disc fork and brake on the front of my Kona Jake, but I don't plan to use it for racing, having just picked up a used Major Jake for that.