Feb. 3, 2013— -- There's more than just a trophy on the line for Superbowl XLVII -- as two sibling head coaches are pitted against each other for the first time, while one of the NFL's greatest players turns in his final performance, and then there's the question on everyone's minds:
Will Beyonce lip sync during the half-time show?
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More than 150,000 fans have flocked to New Orleans for the big game today between the San Francisco 49ers and the Baltimore Ravens, while it's estimated at least 100 million more will watch from home.
The game will be played in the rebranded Mercedes-Benz Superdome, the same venue that nearly eight years ago housed refugees from Hurricane Katrina in squalid conditions, becoming a symbol of the storm's fury and the human suffering that followed in its aftermath.
Today, 75,000 ticketholders will pack the stadium, marking a moment of triumph for the city.
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No matter the outcome of the game, one thing is already for certain: Coach Harbaugh is getting a Super Bowl ring.
For the first time in professional football history, a pair of brothers are leading opposing teams at the Super Bowl.
John Harbaugh, 50, head coach of the Baltimore Ravens, will face off against younger brother Jim Harbaugh, 49, skipper of the San Francisco 49ers.
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The two, with just 15 months difference in their ages, grew up in Ann Arbor, Mich., and both began their coaching careers working for their father Jack, a college coach at Western Kentucky and later at Western Michigan. The brothers are close and consider the matchup, dubbed by sportswriters as the "HarBowl" a bittersweet moment for the family, knowing one will lose.
"It's probably a little tougher emotionally," John Harbaugh said at a press conference last week. "It's a little tougher just from the sense of I don't think you think about it when you're coaching against somebody else; it's more about the scheme and the strategy. There's a little bit of a relationship element that's more strong than maybe coaching against someone else.
"I'll have a better answer for you after the game," he said. "I've never been through this before. This is all new."
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Ray Lewis' Final Game
The game is expected to be the last for Ravens linebacker Ray Lewis, 37.
The former Superbowl MVP and a two-time defensive player of the year, has made headlines on and off the field during his 17-season career.
In 2000, a fight broke out after an Atlanta Super Bowl party, leaving two men dead. Lewis faced double murder charges, however in a plea agreement, the charges were dropped. Lewis pleaded guilty to obstruction of justice and was sentenced to probation. The case against his two co-defendants fell apart and the murders remain unsolved.
Most recently, Lewis was reported to have used deer antler spray and pills, a substance banned by the NFL, to help heal a torn triceps. Lewis has denied taking any illegal substances.
Hype Surrounding Beyonce, Commercials
For non-football fans, today has been dubbed the Beyonce Bowl.
The megastar lip-synced on President Obama's second inauguration, she said in a press conference on Thursday, because she didn't feel fully prepared.
Will she sing live during the half-time show tonight?
Either way, fans don't seem to mind.
A recent poll on the cable channel Bravo asked, "Who do you think will win the Super Bowl?" The 49ers got 18 percent of the vote and the Ravens took 31 percent. Beyonce won with 51 percent.
Alicia Keys will open the Super Bowl spectacle tonight with the Star Spangled Banner before the game.
Football and A-list entertainment aside, the Super Bowl is also the biggest stage for advertisers, who paid as much as $4 million for a 30-second slot.
Kate Upton, a former Sports Illustrated swimsuit issue cover girl, starred in a provocative advertisement for Mercedes Benz that cost $3.8 million.
"It's a fun spot. Why wouldn't I want to be a part of it?" Upton said.
Approximately 28 of the 35 or so advertisers released their advertisements early, The Associated Press reported, hoping to capitalize on social media buzz.
Among the celebrities expected to appear in commercials tonight are Amy Poehler for Best Buy, Seth Rogan and Paul Rudd for Samsung, and "30 Rock" star Tracy Morgan for Kraft.
ABC News' Russell Goldman contributed to this report.