You definitely can, and in Muna's current form, I guess you even should :) The thing is, I have a lot of ideas that will make Muna unique and, hopefully, a lot more usefull, like offline and mobile reading support, content relevance ranking, etc.
It's built on Symfony with a few cron jobs to process everything in the background and sendind the emails through Mandrill. I'll most surely add some kind of queuing mechanism (either with redis or RMQ) soon to handle things more gracefuly.
The design is a paid wrapbootstrap theme called Harp.
The great thing is that emerging (or established actually) technologies and APIs now permit to modelize complex apps topologies and duplicate them at will (I'm thinking VMs and containers here), so the pain you describe is just one automation away ;)
Can you be more explicit? Are you talking about synchronizing the db schema when updating a staging env, or say, sync the schema accross multiple env each hosting a different version of the app?
When I tell people about an automated staging deployment platform (let's not talk about a company yet, even if that is indeed the ultimate goal), they often ask "what does your product do that heroku doesn't?". That answer is simple, it's in the vision of the product. Heroku is production platform, and everything is geared toward great performance, ease of setup and scalability. IMHO, only one of these characteristics is essential to a staging platform: ease of setup.
I think the real added value of a successful staging platform will come from staging specific features, like making everything automated, easing feedback gathering, one-click staging/prod mirroring, etc. Docker and other isolation or virtualization technologies are most certainly a step in the good direction, but that's precisely what I'm trying to mesure with that survey and the discussion around it.