"...the FCC is reminding people that the existing TV white spaces will remain available for unlicensed use."
Not likely, since some of those channels will be redesignated for wireless broadband and consequently become unavailable for unlicensed use. Whatever channels remain unoccupied by TV stations in the repacked spectrum likely will continue to be available for unlicensed use.
As for Ch. 37, it's now occupied by radioastronomy operations because of its particular propagation characteristics, I'm told. I believe Congress tentatively set aside a relocation fund for Ch. 37, but that it's not yet certain those users will be moved. ~ D.