Yep, Amazon is bringing 20k employees. You figure that at least 75% of those workers will be white and or asian, so expect at least 17.5k more whites and asians into the metro area. Add in spouses and such and it's a wrap.
On the bolded, while I get the appeal of this from a COL perspective, I do think it could possibly further widen the opportunity gap for blacks in America. Ain't no Amazons or Googles down in South VA (Hampton Roads/7 cities area). Cities hoard the best talent and ideas, there's a reason people are rushing back to cities. There's also the network effect that cities bring. It may be nice to move down south to someplace "simplier" but while young, I think it's paramount that the black community look for where the best economic opportunities lay.