The national association for amateur radio, ARRL favors WiFi mesh:
... The broadband provider that's been testing BPL in the Village of Penn Yan, New York, ... DVI now is proposing to employ wireless mesh "WiFi" technology instead of BPL. ARRL CEO David Sumner, K1ZZ, congratulated Penn Yan Mayor Douglas G. Marchionda Jr and DVI for going with wireless broadband instead of BPL.
"Not only will your citizens receive better service, but a serious radio spectrum pollution problem has been averted as well," Sumner said ...
http://www.arrl.org/news/stories/2004/07/28/5/