I'm bumping this because I'm in the process of implementing the latest poMMo with a MODX 2.2.0-pl2 site. I'm just setting it up at the moment, but if there's any new ideas floating around out there I'm all ears.
From what I can tell, development is actively moving forward for poMMo. There's an active fork at github, and a new website in the makings. Things seem to be looking up for poMMo. If you've used it in the past, you'll notice some nice changes right away.
https://github.com/soonick/poMMo
http://www.pommo.info/
For the moment I'll be retaining the poMMo UI and databases separate from MODX with some kind of form to database from MODX. I honestly have no idea how that'll go, it's on the list though and I hope it's in the book.
Any thoughts now that we have 2.2.x?