As some presenters curtail offerings for next season, the Kimmel Center has added some. Included in a list of non-classical additions is Berlioz' Romeo and Juliet, performed by the Mariinsky Orchestra (formerly the Kirov Orchestra) led by Valery Gergiev, Feb. 22. The Mariinsky Chorus joins. It's the only non-U.S. orchestra on the Kimmel's 2009-10 season. The other visitors are New York, San Francisco and Los Angeles.