This test flight is launching on a Delta IV Heavy, which is a pretty well proven launch system (first time NASA's used it, though, AFAIK).
Ultimately, Orion's supposed to be launched on NASA's new Space Launch System [1], but it's not ready yet. I believe the first scheduled test flight for Orion and SLS together is supposed to be sometime in 2017.
... propulsion is the interesting part of interplanetary travel. What is the propulsion tech for this?