I'm UK/Canadian. My wife is Canadian/UK. She worked for Pierre Trudeau's Liberal Party as a local organizer. Met him, Cretien, and knew Shelia Copps. Justin's success has been to re-establish the Liberals as the natural party of power in federal Canada. No matter what the details of his success/failure, if he maintains that, it will be a victory.
I should also say that Justin has revitalised Canada for those who shared his father's vision. That vision, I suppose, had a large image of the Canada "we" want. But very short on day to day details.