San Diego prepares for 2012 Comic-Con at the San Diego Convention Center on July 11, 2012. Movie studios aren't all screening new films; some find the convention is a place to make deals without having a high profile. - 

Kai Ryssdal: In San Diego, Calif., this weekend, somewhere north of 100,000 people will meet for the annual gathering known as Comic-Con. It started as a mild-mannered comic book convention 40-some-odd years ago. Over time, it's become nothing less than a pop culture phenomenon. A profitable one at that. Fans, exhibitors and media types will be there as they've always been.

After years of high-profile participation, though, Hollywood's presence is a bit subdued this time around. Never mind that this is the year of "The Avengers" and the umpteenth Batman movie. Our senior business correspondent Bob Moon has more.

Bob Moon: Disney is presenting sneak peeks of Marvel's "Iron Man 3." And Lionsgate is giving "Dredd 3-D" its first public screening at Comic-Con.

"Dredd 3D" trailer: We're gonna have to go through 'em. Rookie, you ready? Yeah. You look ready.

Universal Pictures, though, apparently wasn't ready with any stand-out clips, according to one executive. And the studios have learned that showing off the wrong kind of material at Comic-Con can be a big mistake.

Brad Ricca teaches pop culture at Case Western University. He recalls the heavy promotion Universal gave a couple of years ago to the movie "Scott Pilgrim vs. the World."

Brad Ricca: These enormous banners, and they were giving away free T-shirts and showing the movie, you know, ahead of its release to anyone who wanted to see it -- and the movie came out and it didn't do well at all.

That's not to say Comic-Con fans were the reason for that box office flop. Kendall Whitehouse is director of new media at the Wharton School. From the convention floor, he told me the studios that are there are still packing Comic-Con's 65-hundred seat theater with eager audiences.

Kendall Whitehouse: This kind of fan base is something that can cut either way. If you strike a chord, it can take a film and make it do even better.

Even the studios that aren't making flashy presentations this year are still attending the convention. Again, Case Western's Brad Ricca.

Ricca: All these people go to Comic-Con anyway, and they can, you know, make their deals and search for new ideas and new properties, and do it without preaching to the choir, I think they've realized.

Ricca says the studios have figured out the crowd attending Comic-Con is likely to see their movies, anyway.

I'm Bob Moon for Marketplace.