There may be no bigger video game release this year than Take-Two's upcoming Grand Theft Auto IV on April 29. In fact, it may be so big that it could overshadow certain big ticket movies at the box office.

Janco Partners analyst Mike Hickey believes that Marvel Entertainment's Iron Man, which hits theaters on May 2, could be directly in the line of fire for GTA. You may recall that last year certain execs in Hollywood did refer to Microsoft's Halo 3 for pulling away some box office sales. Hickey thinks GTA IV could be an even bigger deal.

"We anticipate the video game release of GTA IV on April 29th could dampen the potential from Iron Man's theatrical release on May 2nd," said Hickey. "The domestic box office's first week of May release schedule includes Iron Man, Made of Honor, Redbelt and Son of Rambow. The last significant video game release, Halo 3, generated over $300 million in sales from its first week in the market. Halo 3 was released on just one platform, the Xbox 360, and attached nearly 50% of the installed base. GTA IV will be released on both the Xbox 360 and PS3, which have both significantly increased their installed bases since the release of Halo 3. A GTA IV 25% attach rate to a combined Xbox 360 and PS3 installed base at its April 29th release would imply 5.8 million units sold or roughly $360 million in retail sales the first week of the game's release."

Iron Man itself will be receiving its own video game, to be published by Sega.