Well, I got a holy crapload of work done this weekend on Twelve Parsecs. The vehicle rules are progressing well, and I think people already familiar with the system will pick them up instantly. As with most stuff powered by O.R.C.S., they can be as complex (if you include the tactical minis stuff) or simple (if you freeform it) as you like. Generally speaking vehicles work just like characters, with the same 6 Ability Scores (though they combine in unusual ways with PC Abilities--a PC, for example, would make an Intellect check to use a ship's FTL drive, but capped by the ship's Strength, which represents its engines).
Ship combat works off of Ability Checks rather than weapon vs. armor as does man-to-man combat, but I think it works.
Anyway, after I finish with vehicle rules I'll probably get the psychic powers written up--been putting that off. Then I'll decide how detailed I want to get with cybernetics, robotics, and computer hacking systems. After that, "rogue's gallery" and "vehicles" appendices and it should be about ready to move to playtest, editing, and layout.