Creative class guru Richard Florida is guest blogging in Andrew Sullivan's space this week. His first entry ponders where college grads, facing an uncertain economic future, are heading.

He points to Saturday's Wall Street Journal article that noted that young hipsters are still attracted to places like Portland, which at least offer interesting culture if not many job opportunities. Cities with less curb appeal, such as Phoenix, Charlotte and Las Vegas -- all big youth gainers at the height of the housing boom -- are not pulling them in.

Florida suggests that his usual list of attractive cities, such as New York, Boston, San Francisco and Denver, are going to continue to gain in college grads. Given the worsening economy, a "thick" economy is what's most desirable.

The appeal of big cities stems from a simple economic fact - they offer thicker labor markets with more robust job opportunities across a wide number of fields.

Getting ahead in your career today means more than picking the right first job. Corporate commitment has dwindled, job tenure has grown far shorter, and people switch jobs with much greater frequency. The average American changes their job once every three years; the average American under the age of 30 changes their job once a year.

In today's highly mobile and economically tumultuous times, career success also turns on picking a thick labor market which offers diverse and abundant job opportunities. For new grads, picking the most vibrant location is an important hedge against economic uncertainty and the risk of layoff.