Ask yourselves how many stories of sexual maniacs find teens from the net, indicent content on the net, Myspace and internet chatrooms are full of crap. Rabbis have a good reason to be concerned because they want to protect their communities. If you don't see the net to be a problem others that care do. Since there are no effective programs to make the internet secure many parents not only orthodox Jews are worried about their children being exposed to the net.
Preliminary report: Palestinian stabs man near Damascus Gate, Jerusalem (Haaretz)
from the article: Ultra-Orthodox Jewish group declares war on computers