Not worried at all. The cell sites are generally very poorly protected and monitored leaving them open to attack. Piss enough users off and you are bound to get more than a few that are willing to "free up spectrum" from the hijackers that run the cellular companies. These assholes have already managed to grab nearly half of the old UHF TV spectrum after the next auction to verizon and at&t is completed. I suspect that it will only be a matter of time before the cellular companies are able to get the FCC to relegate WiFi to secondary use status behind their own services. In this though they may have a fight on their hands from the cable companies like Time Warner and others that use the installed cable/WiFi routers of their customers to extend their "free" WiFi services to their customer base. Speaking of which, we are aware that cable companies not only charge us to rent their cable routers with WiFi but then turn around and open a WiFi link to service their customers and make you pay for the power to run the service to boot?