This sounds interesting, especially as (now but not forever) the better tiers are free. There will always be a free tier, according to the ads. 

It's trying to be an app store for open source web applications, allowing you to install all sorts of social server apps from Wordpress to Etherpad in sandboxed 'grains' (essentially containers). While there are some similarities between this and distribution systems like Softaculous, the simplicity and relative security of this solution, as well as the fact that the company takes ownership of issues like performance and reliability, makes it worth a look, I think. At the very least, it's a neat way to try out new tools that might otherwise take effort and skill to install.

In the longer term, this is a smart approach to making money from open source and cloud applications. Unlike the big greedy monoliths, it does not take away ownership from its users, and it provides a great deal of flexibility to do things that big social sites cannot support. I hope that it spurs further growth in interoperability between such tools: it's an ideal testbed for such things. It would be enormously cool to, say, incorporate a bit of Wordpress, a bit of Moodle, a bit of Etherpad and a bit of Elgg into a single social ecosystem, without having to hook in to a greedy black hole like Facebook or Twitter.