Variety’s warp up of 300’s box office victory at the ticket selling gates has some interesting quotes — the $70 mil take was a mere $30 million more than tracking predicted. Sheesh!

Playing in more than 3,100 theaters, pic was the third biggest R-rated opener ever — behind “The Matrix Reloaded” and “The Passion of the Christ” — and the biggest R-rated opener in March.

[snip] Fellman said the demos for “300″ were equally split between men and women — surprising, given the project’s high violence and machismo — and he pointed to the pic’s Internet-heavy marketing campaign as a major part of its success. Warners had pushed the pic’s trailer on MySpace and other youth-skewing sites.

Reflecting its popularity across many markets, “300″ played to a per-theater average of $16,500 in Salt Lake City, which Fellman called “home of the PG.” Pic hit $28,000 per engagement in Los Angeles and nailed averages of over $24,000 per theater in Las Vegas, Chicago, New York and San Francisco.

Fellman compared the movie’s success to that of “My Big Fat Greek Wedding,” the 2002 left-field romantic comedy hit that racked up more than $241 million. Pic was another original concept that managed to build a major fanbase though not part of a franchise, a la “Matrix Reloaded”; nor did it attract auds outside the typical moviegoing demo like “The Passion.”

Pic also played particularly well on Imax screens, drawing a $54,500 per-screen average off 62 runs. Imax chairman-prexy Greg Foster said “300″ played into a campaign aimed at the young fanboy crowd.

“We’ve been cultivating the techie crowd of 15- to 24-year-olds who play videogames and watch DVDs,” Foster said. “It’s a (demographic) that’s difficult to get (to theaters), but we finally nailed them.”

300’s production cost was a truly Spartan $65 million, which left a lot for the marketing blitzkrieg. Such a high yield on investment pretty much guarantees that we will be seeing more green screen movies where nothing exists except the six-pack abs.