The Klingon ship looks really cool. Though I haven't really complain about anything Cryptic has given us, the Federation ship looks weird and out of porportion at the front of the ship though I imagine it may look alot better in the actual game. Nice to see some new pictures!
As for the registry.. as it's just concept art the registry number doesn't really matter.. they could have made that before the actual NX-91001.
Are these in-game screenshots, concept art mockups, or something in-between? The shattered planetoid, in particular, looks hand-drawn (yet awesome). The design of the Klingon ship looks somewhat familiar to me, though I can't put my finger on it.