I just saw it today and I thought it was amazing.
I had read the book and seen "Manhunter" awhile back, just before "Hannibal" came out actually. I was really disappointed with "Manhunter," first of all because I loved Anthony Hopkins in SOTL, and Brian Cox did not have nearly the same effect as Mr. Hopkins did in the role.... that monster dwelling within the perfect gentleman vibe that Hopkins exudes as Lecter in both SOTL and "Hannibal" is chilling to the bone.
Having Anthony Heald back as Dr. Chilton (same hairdo and all!) and Frankie Faison back as Barney helped seal the deal, cementing this film firmly as part of the Lecter trilogy.
But most of all I loved that the new movie remains true to the ending of the book. I won't spoil it for anyone who has not seen it, but it is very clever, and I was extremely disappointed when I saw Manhunter that they did not include the ending from the book. Actually the ending of the Red Dragon movie takes things a step further in one sense, and does something that did not happen in the book that I think is extremely clever, it has to do with something Will Graham says to his son that he had just recently read somewhere else.... I realize that sounds very vague but hopefully if you saw the movie you know what I'm talking about.
The whole cast turns in awesome performances... of course Edward Norton and Anthony Hopkins, and also Harvey Keitel, Ralph Fiennes, Emily Watson, and Phillip Seymour Hoffman, all at the top of their game.
To be honest, I think I like this movie better than SOTL and Hannibal. Probably there will be a lot of people that scoff at the notion that this could actually be better than SOTL, but I thought it was.