to me that there are lots of compelling reasons to play it on Saturday, especially if you want to attract more viewers overseas. In Europe, people will be more likely to stay up late on a Saturday night than a Sunday night to watch the game. In East Asia & Down Under, Sunday morning is a much better time than Monday morning, if you want increased viewership (although I've enjoyed my Monday morning Super Bowl parties over the years).

In the States, I think people would appreciate not having to get up early to go to work after a hard evening of junk food eating, drinking, and football-watching. And of course, for the hard-core Mormon demographic, like my mom, (or better said, for their husbands and kids) it would be a gift from heaven.

Personally, I think the switch will happen within the next 10 years, especially if the NFL does put a team in London (which I don't think will actually happen, BTW).