Gangs of New York is perplexing. Certainly more so than any other mainline Scorcese picture to date. On the one hand, you have gorgeous cinematography, beautiful coloring, exceptional set and costume design, and great performances from Leo and Daniel Day Lewis.
On the other hand, though, there's Cameron Diaz's questionable (at best) performance, an at times aimless plot, and sub-par (for Scorcese) pacing.
Additionally, I find Cameron Diaz's character almost pointless. I would personally have cut her with some slight rewrites, which would cut down on melodrama and focus a story which I find lacks it.
Is it worth watching? I would say so, yes. Certainly so for anyone who cares about film enough to use Letterboxd, or to read this review. As for the general public, although I might reccommend it, I do question the attention span; 2 hours and 46 minutes is much longer than it is short.