imperialus said:
Also, I'm wondering how Frodo ends up making an apperance... He wasn't even born yet when Bilbo went to Lonely Mountain.
Short answer, he appears as the narrator of sorts reading Bilbo's "There and Back Again".
Also, on Legolas, there's already debates aboout his appearence and whether or not it was in the book, I doubt it'll be much more than a cameo.
See the thing about Peter Jackson's film making is that he's very sentimental and he loves making throwbacks to his previous films. For example, in King Kong one of the animal cages in the ship is labeled "Sumatran Rat Monkey" and anyone who's seen Braindead/Dead Alive might get that reference. Also casting Sean Astin as Sam was a somewhat sentimental decision as Jackson worked with his father, John Astin in The Frightners, (and Sean's daughter appeared as a Hobbit child in Return of the King meaning Jackson has worked with three generations of the Astin family.) Also, like Alfred Hitchcock, he appears in all his films. The Hobbit gives him licence to indulge a little bit by including characters from the LotR films that may only ever had minor roles if any at all in The Hobbit and Legolas is a good example.