I was thinking the exact same thing. I got through most of the first paragraph, then quickly scrolled down through the article looking for an obvious summary. No luck. I just went back and clicked the link to the Unicorn readme ( http://unicorn.bogomips.org/ ) and that had a decent summary at the top. Still, it would have been much better for this summary to have been in the article also. Perhaps they were expecting anyone who read the article to have already known what Unicorn was.
More documentation on Unicorn is always nice, since it feels a little sparse in places, and sometimes I'm left wondering whether I've overlooked something in my production setup.
Could have used a little more discussion on signals (e.g. USR2 for reloading code) or possibly other daemon control type issues, which I recall doing the most fiddling with.
I'd still like to hook Unicorn up to Munin or Nagios (for historical stats, not process monitoring), but haven't found any resources on the subject.