* No Real Names requirement. * I think we have a single account per email address, but I don't think that's what you mean. Also, you can likely use +whatever on your email addresses if you really want to.
As to centralization -- I'm as worried about centralization of the net as Brewster Kahle, but that's as yet an unsolved problem, and not the one we're tackling with Webmaker. We're (just?) trying to make an app that makes it easy for people new to the internet to see that they can create web content, not just consume it, even if all they have is a low-end android phone and low literacy. The app storage architecture is centralized today, but I'd be happy to explore ways to federate it, once we get to the point where it we've confirmed the app is attractive to its main audience.
TLDR: Sorry, this isn't the droid you're looking for =)
Every time Mozilla gets a product out, I hope it's a privacy-aware social network, with no full-name or single-account policy, with little centralization, which doesn't require installing MongoDB (Disapora I'm looking at you), where I could share some pics. I'll have to wait for the next round ;)