VoIP over WiFi tested for public safety but at what cost?

Very geeky. RoamAD and WI-VOD have just finished testing for VoIP over WiFi up to 80mph in Arizona. This was funded by a Homeland Security grant for public safety personnel.
Slashdot and WNN via MuniWireless

Personal note: Similar to all public safety WiFi networks across the country, the City of Greensboro is deploying a network by Tropos Networks, but I cannot help but wonder why people (especially public officials) do not take heed when applying WiFi to public safety.
As a wireless consultant, I have again and again implored officials to take caution in mission-critical applications over these ISM bands. Not only are these public bands that cannot be allocated strictly for public safety, there is overflow of RF overlap and a bottleneck for bandwidth. There is nothing stopping any semi-intelligent crook to use a jammer for the 2.4Ghz range. Even applying the 802.11 standards flaw would take a tremendous hit on public safety in general. The CERT advisory is published here (2004-13-05).
Note that the standards flaw is within the 802.11 protocol standard when using DSSS (direct spread spectrum sequence) and the 2.4Ghz range. This vulnerability is immune to any encryption scheme since it is at the lowest layer and was discovered back in May of 2004.
Local governments should take heed when applying any mission-critical data on such networks. There is no way to assure quality of service on a publicly shared band with this technology.
Cybercriminals are getting hardier by the minute. Unfortunately, the bomb is ticking and there is no one around to blow out the fuse.