xbox one supports a usb keyboard (i just verified this with a wireless logitech usb one)
I easly navigated ie to m.playon.tv it saw my computer and came right up. However, as there seems to be no keyboard support for the playon interface, i was unable to move through the menu or even select anything. Xbox one does not have any mouse support at this time. if you were to simply add keyboard support to the m.playon.tv interface page, it would be awesome.