This is a 12 team league?
You have question marks at QB but Ryan and Cutler should at least be serviceable. And I don't think the Niners defense is starter-worthy.
Is Burleson a flex starter or WR starter? If you're start three wide receivers, you could be in trouble there because I don't think Morgan, Maclin, or Burleson will put up WR#3 numbers. Josh Morgan surely has the talent to be a dominant receiver, but the 49ers are dreadful at quarterback, and will stick mostly to the ground game, which will hurt his fantasy numbers.
Vernon Davis isn't a fantasy-worthy starter either. He's a backup tight end in fantasy football.
You'll be somewhat competitive, but you should temper your expectations.
[ Edited by crzy on Aug 25, 2009 at 11:32:05 ]