For the last 10 years (until the recent Uncanny X-men re-launch) the Avengers main title has been outselling the X-men.
The Avengers movie is coming out in a few weeks and is set to be really,really massive (probably bigger) than any X-men movie. Iron man 1 and 2 were more successful than any X-movie. Thor and Captain America made roughly around the same thing the first X-film did (unadjusted for inflation).
Iron Man, Thor and Captain America are now household names (The Hulk is already a house hold name so i won't count him).
So, the question is this, are the Avengers now Marvel's number 1 franchise? Can the X-men ever again take that title?
Moderators, feel free to move this to the Avengers forum.