>Who determines product direction?

Everyone submits ideas, some voting and discussion takes place, then people work on what they want to work on.

Splitting equity and revenue is a much more complicated issue. In my experience it's easy to figure this out for small teams, provided the members are reasonable and can appreciate each other's work.

There was a software startup that was trying to do exactly this but I can't remember what it's called. Quirky is also doing this, albeit for tangible products, and they have an interesting approach.