Did the right person win London's mayoral nomination?
Mr Livingstone served two terms as London mayor between 2000 and 2008, polled 68.8% of the total votes.
He will run against Conservative incumbent Boris Johnson. Former Liberal Democrat MP Lembit Opik has said he hopes to win his party's nomination.
Mr Livingstone has said his top priority as mayor would be holding down public transport fares.
Does Livingstone's nomination signify a re-run of the 2008 mayoral election? Is his nomination a come-back to the political scene? Is his pledge to hold down fares a good one? What other areas should be a priority for the London mayor?
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