The porn business generates more annual revenues. Sad to say but you are right, it is close. Below shows the most recent published revenues for each of the Big-4 sports leagues in North America:
NFL (2009-10) - $9.3 billion
MLB (2010) - $7 billion
NBA (2009-10) - $4.7 billion
NHL (projected 2011) - $2.9 billion
Follow-up (rhetorical) question:
To whom does all this money go?
We can pretty much see where the sports money goes, players, advertisers, team owners, media, etc.
I can’t imagine a porn star getting a 5-year $25 million-dollar contract. Are there public porn corporations that disperse dividends?
I’d say follow the money.