Charlotte-Douglas is a major INTERNATIONAL hub, and HQ for American Airlines. It's a top 3-4 financial center and HQ for Bank of America. As per my neighbor who works for ESPN here in CLT, the ACCN will eventually be here permanently, probably as part of a new contract.
There's a continuing rivalry between The Triangle (Raleigh-Durham) and Charlotte. CLT has pro teams in the 2 major sports (Panthers/Hornets) and a healthy number of NE and Midwest transplants- everyone here is from somewhere else.
If the ACC wants a major footprint that'll guarantee viability for the conference for decades to come, you gotta move the HQ to Charlotte. JMHO