I read Hannibal a couple weeks ago, and then read Red Dragon. I just purchased Silence of the Lambs so I'll have to see how that compares. I have seen the movie, but it has been a while so I'm looking forward to reading it. (With no TV, I've been doing a lot of reading!)
I thought Red Dragon was a good thriller, especially at the end. Hannibal was quite a bit longer, but I think it was just as good as Red Dragon. It seemed more advanced, but you're right in saying it was a bit far fetched. The pigs were believable, but not the brain thing. Unless a doctor or anyone else with medical knowledge can tell us otherwise.
If you look through the MGM site for the movie, it shows the pigs, so I guess they're in. They also show a still depicting the small avaition-related scene in the book so that's in unless it gets cut. BTW, one small error in fact here--the book has the flight taking place at night, but as far as I know, almost all of the westbound trans-Atlantic traffic chases the sun in the daylight. Oh well, I can let that slip.
The pigeon scene? Refresh my memory.