Plenty of people writing the French off on the basis that they haven't played well this tournament. This may end up being the case, but I'd simply indicate the following:
In 1999 France had a fairly ordinary pool stage, they managed to beat Canada by 13, Nambia by 30 and Fiji by 9. There were 5 pools in those days and the 5 2nd place getters played the best 3rd placegetter (Argentina) in the quarters. France then beat Argentina (a much poorer team than they are now). No one (including the French) gave France a chance against NZ in the semi. France were a bit of a rabble in the first half and were down 10-24 at half time, before turning on one of the best 40 minutes in the history of test rugby to win 43-31.
In 2007 they lost their opening game to Argentina and beat Georgia, Namibia and a very poor Ireland side, while NZ came through their pool with a 40-0 win over Scotland as their closest match. Again, no one gave them a chance in the quarter final against the ABs.
In both cases, it was the only decent match that the French had played in the RWC. If they can put it together, anything can happen. The ABs on form should win this by 30 points, but......