"because there will be millions of people NOT in Pittsburgh or Seattle that will tune OUT..."
Most of the NFL is in "small markets." IMHO most Football fans are just that -- they love the game and have some favorite teams.
The SB will draw well, maybe not record-setting -- Steeler Nation is much larger than most people realize.
You do have a good point....and that Seattle being a first time team...SHOULD up the interest level more than Carolina would, I think...
And Cowher vs. Holmgren...is a good coach/coach matchup.