The original Star Tours attraction opened in Disneyland two years before the same ride opened at the Disney-MGM Studios, but this time around, Walt Disney World will have the first run. Star Tours: The Adventures Continue will open at Disney's Hollywood Studios on May 20, 2011 but wont open in Disneyland until June 2011.
The opening of Star Tours: The Adventures Continue at Disney's Hollywood Studios on May 20th will coincide with the start of Star Wars Weekends and will include Star Wars celebrities Anthony Daniels (C-3PO) and Ashley Eckstein (voice of Ahsoka).
Further opening details are not yet known such as soft openings or Cast Member preview, but Studios Central will provide live coverage of any and all openings including the grand opening on May 20, 2011.
Tip of the hat to Inside the Magic for the Disneyland info