Mark,
At the moment it is just a bunch thugs quite literally running riot, which has now snow balled into copycat riots in different cities. The worry is that if these people find a cause, like social exclusion, joblessness etc and it turns political, well then were are in trouble. Take the Arab uprisings, they were all started by disaffected young people and look where that has ended up.
I think David Cameron has done well today, upping police numbers to 16,000 from a mere 6,000 but the police need to be careful they don't fan the flames with excessive use of force. All bleek stuff.
Simon