Like many I read the headlines about Pinterest moving from Palo Alto to San Francisco and thought about the trend it portends. For those not familiar with the local geography, Palo Alto is the north end of what most consider “Silicon Valley” although nobody local calls it that. Palo Also is about 35 miles south of San Francisco.

Palo Alto is home to Stanford. It is the birthplace of Hewlett Packard. And Facebook. It is adjacent to Mountain View, home to Google. Further to the south are the legendary companies of Cisco, Apple, Intel, eBay, Yahoo!, Juniper and countless others.

Back in 2006/07 when I sold my company and then worked at Salesforce.com there were very few options in SF for technology folk to build their careers at big, growing companies.

Today there’s many. In addition to Salesforce.com (the 800 pound gorilla) there is also Twitter, Zynga and Square – just to name a few. And now Pinterest.

So why all the movements towards cities? It’s clearly more expensive for office space and living. In addition to higher rents many cities impose city taxes on local businesses. It’s clearly a complex topic without black-and-white answers.