Actually the site does not claim to build open-source products. They want to use open-source methodology to collectively build and commercialize SaaS products/apps.

To ensure collaboration is easy the code is open-source. To ensure contributors get paid for their work we'll run a hosted version and allow companies to run it themselves with a commercial license.

I stand corrected - Now I see it is like developing AGPL products by a group of individuals/community. Interesting concept, reminds me of an idea pitched to me few years back.