"Actually, we haven't talked about it at all," composer-lyricist Stephen Schwartz told Playbill.com. "My assumption has been that because [Wicked producer] Universal is a motion picture company that eventually they are going to get around to wanting to talk about a movie, since they have the right of first refusal on it. But at this point it's still kind of early in the game for us. We're just starting to launch some of the foreign productions and it remains to be seen the extent to which this will translate outside of he United States. We're going to learn that over next couple of years."

Rabid fans of the musical, based on the Gregory Maguire novel, which tells the backstory of the witches of "The Wizard of Oz," are likely already making up their speculative lists of who should play Elphaba and Galinda (aka Glinda) in any future movie version.

The novel "Wicked" has a sequel by Maguire, "Son of a Witch." Will Schwartz take a stab at a musical sequel?

"Everybody asks me that," he said, patiently. "Of course, that's not the reason I do things. I did like the sequel. And I've actually suggested to Gregory Maguire that he make that the second part of a trilogy. He said to me, and I believed him, that that had never entered his mind, but it seemed clear to me when I read it there was a third part yet to come, which I will look forward to but don't expect to be musicalizing."

Schwartz, 58, called Wicked "sort of a nice bookend" to his career, which began in 1971 with Godspell. "I've been associated with two shows that became phenomena in my lifetime," he said. "They were my first [Godspell in 1971] and, at this point, my last [Wicked in 2003]. There's a nice, neat arc to that." Will he never write another musical?

"You never know what you're gonna do," he said. "My big project now is that I've taken on an opera commission [Opera Santa Barbara's Séance on a Wet Afternoon in 2009]. That's certainly going to occupy the bulk of my attention for the next several years. When I come up for air from that, we'll see where we are. Listen, I wasn't looking for a stage musical to do when a friend mentioned that she was reading an interesting book and it was called "Wicked." It was the idea itself that seemed irresistible to me, and particularly appropriate for me. You never know when another idea like that is going to come along, and when the medium it's going to demand is a stage show."

When Schwartz sought the theatrical rights to the novel "Wicked," he learned Universal Pictures had them sewn up. "I was lucky because it was Universal, and it was Marc Platt who was running Universal," Schwartz said. "…He had an affinity for musical theatre and therefore was not deaf to my entreaties that what this needed to be was not a movie, but musical theatre. Eventually I was able to persuade him to go that route. It's been quite a ride."

Having the idea to turn the book into a musical, and being able to see it succeed as a phenomenon is something he is "dazzled" by, Schwartz explained. "Obviously when you touch a chord like that, it's very gratifying for a writer," he said.

For more information, visit www.wickedthemusical.com.