As Jno says, there doesn't appear to be a large radical presence in Egypt, and unlike Iraq, Iran and Pakistan, Egypt seems only in the past five-six years to have tipped into serious poverty and unemployment - the breeding grounds of radicalism and unrest.
Prior to that, although most people were poor they could afford food and a home, you didn't see hungry people and most people seemed contented. When I last went to Cairo in April there was an edginess I hadn't seen before, and reports of poor farmers being kicked off their land by wealthy landowners were abounding.
The use of mobile phones and the internet has I think empowered ordinary people in Egypt, and having seen the exampe of Tunisia I suppose there has been a great feeling of 'what is there to lose?'