The video-game industry has been living on a prayer all year, but Activision (ATVI) managed to squeak past expectations with a solid third-quarter earnings report. Fourth-quarter earnings guidance was just shy of consensus, but that's good enough for an industry that just saw the Nintendo Wii and music-game bubbles burst.

What's keeping Activision afloat are two things -- lowered expectations and Tuesday's release of Call of Duty: Modern Warfare 2, which should quickly win the title of biggest opening week for an entertainment release in history. According to BoxOfficeMojo.com, Harry Potter and the Half-Blood Prince holds the global movie box-office record with a $394 million opening week. Counting pre-orders, Modern Warfare 2 could crush that number within a couple of days.

If Take-Two Interactive's (TTWO) Grand Theft Auto IV could do $500 million in opening-week sales, Modern Warfare 2 should be able to do $1 billion, given the larger installed base of Microsoft (MSFT) Xbox 360 and Sony (SNE) PlayStation 3 consoles, and a modest boost from PC gamers.

But will it really be the biggest entertainment release of all time?

Can Modern Warfare 2 top the armies of weeping girls and dragged-along boyfriends that drove Titanic to a $1.842 billion global box office?

Let's do the math:

At an average unit selling price of $70, Modern Warfare 2 would have to move 26 million copies to beat Leo and Kate. At $60 a pop, 31 million units, and at $50, 37 million.

Figuring out the average selling price is the trickiest part of the equation. Activision will sell iterations of Modern Warfare 2 that cost $80 and $150, but overall, the normal $60 version should reign supreme. Plus, the game's price could drop after a few months, particularly the PC version, which is being knocked for a lack of PC-centric features.

So to be conservative, I'll settle on an average selling price of $60 for the console version, and $50 for the PC version. Forgive me if I'm not being particularly rigorous here, but I'm not figuring out the cost of continuing the war in Afghanistan or the tab for the public option.

The Xbox 360 and PS3 should have a combined installed base in the neighborhood of 55 million to 60 million units by the end of the year, a number that will steadily rise in 2010. I don't think it's crazy to assume that Activision could sell 25 million or 30 million copies of Modern Warfare 2 for the 360 and PS3, with PC gamers kicking in a few million more. Add it up, and it could be enough bucks to push the game over Titanic's $1.8 billion number.

While that's good enough for the inevitable declaration-of-victory press release from Activision, I'm still going to rate Titanic as supreme.

Why? Inflation, popcorn, DVDs, and VHS tapes.

According to the National Associate of Theater Owners, the average ticket price is up 56% from 1997. That's a lot of inflation.

Plus, the average Titanic viewer (and her dragged-along boyfriend) bought at least a few bucks worth of junk food at the theater, and at least rented or bought a copy on DVD or VHS.

So in today's dollars, consumers probably spent more than $4 billion on Titanic. That's a heck of a lot more than will ever be spent on Modern Warfare 2, even counting used games, a few people becoming inspired to get a new console, and complementary purchases like Xbox Live subscriptions.

US Marines and Special Air Service commandos kick butt in real life, but their video-game counterparts are simply no match for a steamy big-screen romance set to the sultry sounds of Celine Dion.