I can't imagine the video wall would last terribly long each time, since it has to be turned up very brightly in order to be seen on camera underneath all the bright studio lights. Even then, at its best, it will never appear as sharp or as bright as a map on chroma key.
It was a nice idea they had about the video wall, but putting it into practice has shown that maybe it's not the best way to do things after all. They realized that the maps just looked too murky on the wall, so they started using chroma key again. They realized that the wall has to be maintained far too often (and usually at great cost) in order to keep using it.
I think it's time to just abandon it altogether. Unless NBC is giving money for them to burn... with the provision that they don't spend it on payroll (referring to the many recent layoffs of longtime staff).