I've you happen to be in Central Europe - you're invited to join us for the 4th (last before the summer) Vienna.html meetup (free, everyone welcome) on Tue, Jul/28th. Talks about Middleman so far include:
Real World Static Site Showcase - Inside Contentful - Turn Your Blog Posts into Facebook Instant Articles w/ Middleman by Rouven Weßling (Contentful)
Summary: Facebook Instant Articles is a new way for any publisher - including you - to create fast, interactive articles on (mobile) Facebook. Rouven will show how you can prepare and auto-build Facebook Instant Articles web feeds (in RSS) from your blog stories (in Markdown) with the Middleman static site builder as working live on the Contentful blog. Rouven will discuss alternative strategies and go through some of the possibilities and limitations of Facebook Instant Articles. PS: Rouven will start off with a short intro about what's Contentful anyways? And how you can use the Contentful service to manage your (static site) content.
Bio: Rouven Weßling is a Joomla! developer turned front-end developer and is now a developer evangelist for Contentful. When not programming you most likely find Rouven eating cake or running on the streets of Berlin (so he can eat more cake).