It was mentioned during the NDP leadership that Mulcair didn't come out with many policy ideas, in my opinion it's not necessarily the place up decide policy.
I think it may be a good thing for the Liberals to have a leader who hasn't release a ton of ideas him or herself. Ignatieff's writings and comments came back to haunt him.
Yesterday's poll showing how popular his father remains also bodes well for him. He wouldn't be my pick for Prime Minister but he could revive the Liberals.