A child-star first Oscar-nominated at 19, Leonardo DiCaprio has"'come of age'" with every movie since then. On eco-ethics, Martin Scorsese and even growing up, he's every inch the leading man these days--and far too charming to brag about his new nomination, for "Blood Diamond." "I aggressively went after 'Gangs of New York' to try to work with the guy, because I remember seeing 'Taxi Driver' at a very young age when I was about to work with De Niro, and I remember saying to myself, 'wow, I've never forgotten that I was an audience member when watching a movie before.' I've never felt that suspension of disbelief dissolve. I felt like I was in that character's head." Carole Cadwalladr reports.