I thoroughly enjoyed the film. I had heard that it was a different type of film than SOTL and it was, but it was well thought out and put together nicely.
Anthony Hopkins was perfectly suited for this role, and his performance was excellent. "That other woman" was Julianne Moore, and though she did a convincing job as Clarice, it would have been a much different (read better) role had Jodie Foster chosen to take the part.
As far as gore goes, I was expecting worse. I mean, the final scene was more surreal than "gross". And the other scenes depicted events that are historically accurate. This is not your typical slasher movie (as people have been making it out to be).
If you're expecting to see SOTL, Part II you'll be sadly disappointed. But if you like the premise that SOTL is based on, you'll like Hannibal.