Sounds like a very interesting idea, I look forward to reading the rest of the series. I would imagine that it would be a good way of getting new customers if you were running the business properly, since people can make their own judgment on how well they trust the business owners.
One very interesting effect of allowing anyone to become business contributors is how it could change staff recruitment - you'd have a way of finding candidates who had not only a proven track record of good work, but also have extensive domain knowledge.
Here's a TL;DR I prepared ;)
Open models for value creation work. Look at open source projects, Wikipedia, Kickstarter projects and many others. Lean Startups and Customer Development approaches are pretty open too and we are increasingly seeing open data and open, transparent support ... but how far can we go? Can we open up everything in a startup from idea generation to planning, discussions, financial and testing data? What would an "open source" business look like?
One very interesting effect of allowing anyone to become business contributors is how it could change staff recruitment - you'd have a way of finding candidates who had not only a proven track record of good work, but also have extensive domain knowledge.