This is a freight train and it doesn't seem to be stopping anytime soon...
This is a really interesting model. Can't wait to see how it works out.
Also curious to see how it works out, but this model isn't novel. Shopify has done similar things in the past for its ecosystem. I ended up getting funded to build a Shopify app, and they were pretty easy to work with. As far as I can tell, this offering is no longer available.