Abstract Appeal has this post with a link to an Eleventh Circuit opinion that says you can't just incorporate by reference in appellate brief the briefs you filed in the district court.
Geez, I've got a case in the Sixth Circuit right now where the pro se appellant did just that. In fact, he didn't restate any of his district court arguments, just wrote about the facts and his new arguments, then listed his earlier briefs. Hmm . . . .