Why is private education used as a stick to beat Cameron?
I don't think private education is an issue. What I believe to be the issue (and maybe I've missed the point) is that Cameron has tried to cultivate the image of being just 'one of us' - a normal bloke.
Like I said at the start of this thread, we don't now the effect of viral campaigning as it has never really been used in a British election before. If somebody pulls their finger our and uses viral campaigning effectively there could be a real advantage.