Good question, indeed!
A mini desktop doesn't really interest me (probably not powerful enough to be a headless video-encoding engine, plus I already have one of those; not powerful or full-featured enough to be my main desktop, plus it's not portable like my MacBook Pro; yet too big, powerful, and complex to be my media centre). But there's nothing else like the Astro — nor even anything very much like the Gemini or Cosmo — and that's a class of device I've been using for almost 30 years, and will continue to need for decades to come, so I _really_ hope it doesn't end with the Astro!
I don't know enough about mini-desktops to judge how this new device compares to the competition… Is the spec competitive? Ditto the price? Is it likely to appeal to the professionals, developers, gamers, and/or content creators that they claim?