The reality is that most regions export their talent. [Kevin Stolarick (Martin Prosperity Institute)] developed a measure called the Brain Drain/Gain Index that compares the percentage of an area's population in college to the fraction of college grads in its work force. The upshot: Ten per cent of regions are brain gainers; nine in 10 experience brain drain.
The university's most important role today may be in terms of the third T: tolerance. Societies flourish when they are open to new people and ideas, while stagnating during periods of insularity and orthodoxy. Creative people vote with their feet and they tend to move away from communities where their ideas and identities are not accepted.
The lesson is that the geography of talent is spiky. Vital human capital is pooling in a small number of places that can absorb tech graduates seeking jobs (e.g. Google); provide ample innovation (universities); AND promote creative thinking (tolerance). Pittsburgh is short two of the three ingredients and the result is brain drain.
I still contend that Dr. Florida overstates the push factors of talent migration and that policies designed to retain homegrown human capital are misguided. Brain gain or drain is a function of net migration, not an indicator of a region's ability to keep people from leaving. Since the post-industrial exodus ended, Pittsburgh's problem has been and is attracting talent.
My theory is that human capital seeks places where the world is most flat. A city could meet all three of Dr. Florida's (necessary but insufficient?) conditions and remain a location of brain drain. Perhaps the university assets are being misused, but the fundamental problem is a lack of global connectivity. I notice a strong sense of isolation in shrinking cities. Richard Longworth does a great job of describing this phenomenon.
Local universities are effective gateways to globalization, but how does that help you once you graduate? Most people must pack their bags and head to the spiky world. What is your city's Globalization IQ or Connectivity Profile?