I prefer Ed's politics to David's, but think David would have made a better leader. Like it or not, we now have a quasi-presidential system in the UK, and Ed hasn't got the skills or charisma of his brother. I watched his first speech as leader and was rather underwhelmed; it had all the hallmarks of Gordon Brown's speechwriting team and the delivery was pretty poor.
I fear that at PMQs and other parliamentary set-pieces he's going to be bested by Cameron.
The Iraq issue is something of a canard. Although he was not an MP in 2003, when the vote was taken, he has since had an armful of opportunities to take the high moral ground - yet until the leadership debate he has been very quiet on the issue, and would not even vote for the establishment of an inquiry into the war.
As Peter says, he's no 'Red Ed'; in fact his record is pretty right-wing. He has consistently voted in favour of ID cards, in favour of ministerial powers of intervention in coroners' inquests, in favour of Labour's programme of post office closures, in favour of reducing the powers of Parliament and so on. His voting record can be seen here.
Although a natural Labour supporter (and former party member), I really can't see his portrait going up on the staircase at Number 10.