I wonder if this investment by Google Capital signals upcoming legal/regulatory challenges for Google Corp. In theory Google Local should be able to upend the Thumbtack business model by driving significant organic search traffic directly to local businesses.

Google bought Zagat to go head to head with Yelp and now gives Zagat reviewed restaurants premium search placement atop a ticker. Why not follow the same strategy for local services?

I find it interesting that the one company that can do the most damage to Thumbtack puts ~$100m into the company.