"Gangs of New York" looks like a very good movie to watch, but i have no clue what the whole story's about. So here's my question: What's it about? If any of you know what the inside scoop is....

All i know is that there's an Italian gang and an Irish gang in the early 1900's of New York starring Leonardo DiCaprio (*gag* not too fond of him) and Cameron Diaz.