A lot of these guys used to work for Rotary Rocket, and there are some red-hot rocket engine designers there. I'm rooting for them, and can't wait until they roll out the next generation. Given their reluctance to tout things that actually haven't been built yet (probably a leftover case of jitters from their Rotary Rocket experience), the first you may see of their next ship is when it's sitting on the tarmac.

I know no more about it than anyone else at this point, but I'd bet their next bird will look similar to this one, which I believe is from a Boeing-Orbital Sciences proposal (just add windows):