We now have our Time Capsules in hand and will be working diligently to design a proper mount for it. As soon as we have something viable, we'll let everyone know. Here's a few notes so far:
1. There is no external power brick. There's just a power cable that's about 6.5 ft (~2M) long. This means that, for mounting, it can't go too high without using some sort of extension cord.
2. Time Capsule has the same dimensions as Apple TV. Our tvTray works beautifully with it nearly as-is, but it would only work in a vertical mounting application.
3. Time Capsule is much heavier than Airport Extreme. As such, any horizontal mounting will require extra support.

Other than that, we haven't even fired the ones we have up yet. Those of you waiting, the good news is that we now have something to measure against. Just give us a little time to confirm that everything works as advertised and we'll get a product to you ASAP.