Both "Spamalot" and "Avenue Q" did this.
Both shows established "permanent" companies in Las Vegas and, therefore, determined that the touring versions of the shows would not tour through the western states. A western tour would compete with the Las Vegas show, you see. Anyone in California who wanted to see "Avenue Q" or "Spamalot" would be willing, they assumed, to travel to Las Vegas. (Never mind that I've personally not been to Las Vegas since 1990, and I wouldn't go there just to see a show. Maybe I'm not their target demographic.)
To add insult to injury, both shows were shortened for Las Vegas. In order to boost ticket sales, they made the shows run 90 minutes without intermission, so that audiences would (literally) sit still for them.
Apparently, the experiment didn't work out they way they hoped it would. Both "Avenue Q" and "Spamalot" closed in Las Vegas after several months of only moderate success.
Which means that both shows are now able to tour California (and other less important states). "Avenue Q" came through San Francisco last summer. And, according to the San Francisco Chronicle, "Spamalot" is now scheduled to stop in San Francisco as well. Apparently, it will arrive in April 2009.
[UPDATE: According to the Shorenstein Hays website, it's not actually going to be April, but rather June 2009. Also according to SHNSF, Spring Awakening tickets go on sale on July 20 -- the show runs from September 4 through October 12.]
[UPDATE 12/22: SHN now says that tickets go on sale to the general public on February 27.]
[UPDATE July 2009: Show is closed, moved on down the road, currently in Los Angeles, as of this update.]