There's a good article describing in detail the efforts made to allow all 68K fans access to video and internet over wifi.
http://arstechnica.com/information-technology/2013/03/the-49ers-plan-to-build-the-greatest-stadium-wi-fi-network-of-all-time/
Most of it is about Wi-Fi, but here are a few cool details:
* 680 access points (1 for every 100 fans), mostly on 802.11ac 5GHz 20MHz channels
* No bridging of access points, so all IP traffic is effeciently routed
* 40-GBit fiber backbone
* 1700 Bluetooth "beacons", unclear if it's limited to Apple's iBeacon technology
* Order food/drinks via app, have runners deliver it to your seat
The relevant part to our group is this snippet:
"Besides building its own Wi-Fi network, the team will build a carrier-neutral distributed antenna system to boost cellular signals within the stadium."
I don't know anyone involved with that stadium, but would be interesting to learn what Sprint and other carriers have deployed there.