According to the data sheet for the WiFi chip in the PS4, it supports 5ghz. I'm hoping Sony unlocks it in a firmware update.... unless they didn't connect the leads....
Chip report
http://www.chipworks.com/en/technical-competitive-analysis/resources/blog/inside-the-sony-ps4/
Data sheet
http://www.marvell.com/wireless/assets/marvell_avastar_88w8797.pdf
Chip report
http://www.chipworks.com/en/technical-competitive-analysis/resources/blog/inside-the-sony-ps4/
Data sheet
http://www.marvell.com/wireless/assets/marvell_avastar_88w8797.pdf