We can't and will not underestimate Bayern. They are a very strong outfit, and one of the big 10 teams in European football.
However, having said that, we are Juve, and aiming for anything less than a victory is unacceptable, regardless of the opposition or the venue.
Ribery, Robben, Lahm, and possibly Olic and Mueller will cause us problems, but I see our midfield owning theirs (if the players are focused, motivated, and fit), and our attackers should really pile the pressure on their defense, as that is clearly their weak point.
I expect Bayern to get at least 3-4 dangerous opportunities in this game, and score a goal. Nonetheless, I also expect Juve to place their defense under enough pressure and create enough opportunities to nick a goal or two.
Ribery, Robben, and whoever lines up in attack will not obviously have it all their way against Zebina, Grosso, and the central defensive pairing of Chiellini and Legro as these guys are seasoned veterans, and not some amateurs acquired from a Sunday kick-about team. I do however think that that the aforementioned attcking trident of Bayern will eventually break through, particularly since they are playing at home, and are supremely talented. I would've felt a lot more comfortable had Canna been fit for this game as well.
I am hoping for a 2-1 win, but I believe that it will end 1-1.