Beyond the personal ties, I find the whole concept of regional diasporas fascinating. When I was building a company here in Utah and hiring was tight we specifically targeted the Utah diaspora. We’d tell our recruiter “find us someone with these skills living in the Bay area who wants to come home to the motherland.” It worked surprisingly well.
Pittsburgh's talent labor market isn't as tight as Utah's, but Phil Windley's targeting of the Utah Diaspora demonstrates the value of connectivity. Utah eventually did see a return on its investment in human capital, despite the brain drain.
Diaspora networking is half of the economic development equation. Utah still lacks the necessary infrastructure to fully utilize its Diaspora. However, that oversight is currently being addressed. As the two networks mature, Utah will have a stronger hand in the global competition for talent.