The 2.4 GHz band is very crowded here in my condo complex. I can see about 20 APs, most of them are Uverse gateways that have wifi turned on by default (even if their wifi is never used).
There is only one other user on the 5GHz band.
When this new bandwidth becomes available, manufacturers will have to make new models of routers and adapters. This may take a long time. If you try to find a 802.11n "final" router it is still very difficult; everyone is still selling old 802.11 "draft" models.