One of the more spammy areas in Google is the Google Maps results for locksmiths. Google told the top contributors, including Mike Blumenthal that they are now testing in the San Diego region a new "advanced verification" process for locksmiths and plumbers.
Those locksmiths and plumbers in that region will have to go through a more detailed maps verification process. They have until November 10th to complete the verification process correctly and if they do not, their listings will be removed.
Google's help document describes this as:
Google wants to provide useful and comprehensive local listings to people when they search for businesses. Unfortunately, we’ve identified a number of fraudulent local service businesses, including locksmiths and plumbers, who use false identities on Google.
To help reduce fraud and improve the overall experience for you and your customers, we’re now asking businesses to pass an advanced verification process. The process is simple—answer a few questions about your business and complete an application with Google’s third-party verification company.
After passing advanced verification, your business listing will continue to be eligible to appear on Google Maps and the Knowledge Panel.
Here is the process to do the advanced verification process. Google is using a third party company named Pinkerton to do the verification. They normally will take less than two weeks to complete the verification process, the documents say. Here is an FAQ on this.
I hope this works but it doesn't seem that scalable for Google Maps.
Forum discussion at Google Webmaster Help.