We've had this discussion on every page of this thread. The only way to do so would be to have sparse dialog of cut scenes. There are probably as many events as in the LOTR trilogy, especially if you add the White Counsel and Gandalf's travel to Dol Guldor.
Unexpected Party and Bilbo's Decision
Riddles in the Dark
House of Beorn
Spiders of Mirkwood
Stealing from and Killing Smaug
Elves of Mirkwood
Battle of the Five Armies
The Battle of the Five Armies is, what, a page or two in the book? I don't think it's unreasonable to make it an epic battle. The Unexpected Party alone will probably be the first act in the movie based on traditional movie structure. Given this, those two scenes would take up around 2/5 of a movie.
ETA: For what it's worth, my friend informs me that the Hobbit audiobook (or audio drama, not sure which) is six hours long.
ETA2: Nevermind, it's Eleven Hours and Eight Minutes
- Damn, Peter Jackson looks like he's going to cut everything out if he wants to squeeze it in only nine hours.