Montreal's point total, 2007-08, excluding games vs. Boston: 88 in 74 games
Montreal's point total, 2008-09, excluding games vs. Boston: 89 in 76 games

Boston's point total, 2007-08, excluding games vs. Montreal: 93 in 74 games
Boston's point total, 2008-09, excluding games vs. Montreal: 105 in 76 games

Points gained in Montreal-Boston season series, 2007-08 (max 16): MTL 16, BOS 1
Points gained in Montreal-Boston season series, 2008-09 (max 12): BOS 11, MTL 4

This rivalry tends to throw reason out the window. The Habs aren't much different vs. the rest of the NHL this year in comparison to last. The Bruins improved not only against the Habs, but against everyone else as well. The rest of the NHL does worse against Boston than against us, not only this year, but last year as well. The Habs really aren't any worse than they were last year... Boston is simply that much better. 

If you wanted to talk the difference in the Habs' GF/GA ratio from last year to this, again, look at this season series.  The Habs won several games vs. Boston last year by 4 or more goals.  This year, they only won once, in a shootout (which is a tie on the GF/GA card).  I'm sure if you broke down the team's PP differential, a lot of the difference between the two seasons would be accounted for in the MTL-BOS series. 

If Montreal were to win this series, you'd have to think their chances of winning the Cup are about the same as they were a year ago.  The only advantage lost from then until now was the difference in standing, meaning the Habs got a more favourable draw a year ago, and that they have lost home ice in Game 7.