For streaming I'd think most homes would be limited by their internet speed first though. You may get gigabit wifi link speeds, but what good is that when your provider feeds you 20Mb/s. Now if you had localized content, say full 1080p video on your computers streaming to the ATVs and file transfers and whatnot, that speed would sure help.
Great review of the 5G Gibit WiFi literature.
This thread is getting me even more confused with what's what in measurement of speed. All I know is my ISP the only reason we are getting slow connections here, not my router.