OK, this is neat, BUT a couple of things:
A) If I'm too paranoid to trust a 14 character password to protect my wireless LAN, offshoring my AAA to some site on the internet isn't going to work either.
B) After reading a translation of the about page Google Translate I noticed something important. The goal of the site isn't to make your network 'more secure', it's to allow you to share you internet with select people and still have control (i.e. not sharing your one key with everyone.)
C) Setting up a RADIUS server isn't expensive. "Pourquoi le service WifiRadis est-t-il gratuit ? ("Why is the service WifiRadis he free?) Parce que personne ne va payer pour cela, cela ne vaut pas un radis. (Because nobody will pay for it, it is not worth a bean. )"
D) WPA2-Personal is really damn secure even if you capture the 4 way handshake. The only weakness is users who don't set up good passwords. Any DOS that can be performed against it without the preshared key can be performed against a WPA2-Enterprise.