I have to admit, aethestically it appeals to me, especially that silver lens on the black body. Wow.
I don't know how the image quality will compare with, say, the Ricoh GRD III or the Panasonic LX5, which use a larger sensor and have dedicated (read: made specifically for the sensor) lenses, but I'm willing to wait and see.
The fact that the lenses don't seem to cost that much point to two things: the disposable/novelty nature of the lenses and low cost of manufacture. I hope that this does not translate to low build quality or reliability. The body itself is where the money seems to be, and yet in all other interchangeable lens systems, it is the body that is the upgradable part. The lenses stay with you through several bodies if possible in traditional SLR/DSLR/CSC systems. I wonder if Pentax aim to do the opposite, or something thereabouts: keep the body, and buy as many novelty/inexpensive lenses as you want.
It does seem a rather large amount of money to pay for a camera that can be matched with a couple of high quality compact cameras, but then, the same could be said for the Ricoh GXR. And I love mine. The Pentax Q might serve a niche of people who love gadgety things and are happy with small sensor image quality. The issue that I see is that it doesn't exist in a vacuum, and must compete with fixed lens compacts.
If I was starting a compact camera collection right now, I would buy the Ricoh GXR with two aps-c modules, and the Sony HX9V. I don't think I'd get the Pentax Q, as cool as it looks.