James Cameron's Avatar continues to be sweet celluloid for IMAX (NASDAQ:IMAX).

Sure, News Corp.'s (NYSE:NWS) Fox is the studio behind the popular flick, but IMAX has been the real winner in the film's run. Avatar became the highest-grossing flick -- worldwide -- last week. It likely took the domestic crown last night.

These tallies wouldn't have been possible without IMAX  because Avatar topped the $150 million mark in ticket sales at IMAX theaters worldwide over the weekend.

The really juicy nugget for IMAX here is that its premium screens continue to take market share from traditional multiplex exhibitors. The 179 domestic IMAX locations screening Cameron's blockbuster account for just 2% of the screens showing Avatar, yet clocked in with 21% of the box-office receipts.

This is great news for IMAX, obviously. If there is any studio pondering a tent-pole release, it realizes it's unlikely to get there without a digitally remastered IMAX version.

It just isn't a coincidence that the top flick in each of the past three years -- Avatar in 2009, Time Warner's (NYSE:TWX) The Dark Knight in 2008, and Sony's (NYSE:SNE) Spider-Man 3 in 2007 -- has been released simultaneously in both traditional and IMAX formats.

The streak is likely to continue in 2010. When Disney's (NYSE:DIS) Marvel teams up with Viacom's (NYSE:VIA) Paramount to put out Iron Man 2 in May, it will be blown up on IMAX. Disney's Toy Story 3 and DreamWorks Animation's (NYSE:DWA) Shrek Forever After will get IMAX 3-D treatments a month apart.

It's the network effect in motion. As more blockbusters go the IMAX route, the bigger the draw for multiplex owners to turn to IMAX to beef up one of their screens. Moviegoers aren't shying away from paying a premium for IMAX (and an even bigger markup for 3-D), so box-office grosses grow even more.

Just like Avatar, IMAX is on top of the world.

Have you had a good or a bad IMAX experience lately? Share your perspective in the comments box below.