Cities all over the country are wrestling with how to deal with the sharing economy and its informal, peer-to-peer transactions. It's so interesting to watch these things unfold.

Last month, the California Public Utilities Commission passed new regulations legalizing ridesharing companies like Uber, Lyft and Sidecar. Last week, New York City regulators overturned a $2,400 fine against a guy who rented out his room on Airbnb—although short-term rentals are still illegal here. Some cities "get it."

Some cities "get it." They see the sharing economy gaining momentum, and they realize it's unstoppable.

The smart ones realize that tons of their own residents are using these platforms—that people are generating real income with these activities. (More than 50% of Airbnb hosts in San Francisco rely on it to pay their mortgage.)

Which regions will adapt their regulations to let these companies to grow, and which will try to clamp down on all this sharing?

I've talked about my feelings before—the places that are early to recognize the importance of this economic movement will be the ones that create thriving local economies, full of micro-entrepreneurs and independent workers. 50% of Airbnb hosts in San Francisco rely on it to pay their mortgage.

Here's a report in that same vein: Shareable and the Sustainable Economies Law Center laid out a whole policy road map for creating "shareable cities."

California officials acted pretty quickly—we’ll see how long it takes other municipalities follow suit.