This coming June (from 6/13 to 7/19) the Ravenna Festival unleashes the might of Riccardo Muti & Friends: Muti himself will conduct Berlioz (the Fantastique and Lélio, with Muti BFF Gérard Depardieu as special guest); Muti will also conduct Orchestra del Maggio Musicale Fiorentino in Rossini's Stabat Mater (the singers: Olga Borodina, Angela Gheorghiu's glorious understudy last year in Chicago la signorina Elaine Alvarez, Mario Zeffiri, and Ildar Abdrazakov).
Yuri Temirkanov -- aka Opera Chic's Uncle Solly -- will conduct the Bolshoi Orchestra in a Tchaikovsky/Borodin concert, Kurt Masur will lead the Orchestre National de France in a night of Beethoven symphonies (V and VI),
Other big names: Svetlana Zacharova, Angelika Kirchschlager (a recital).
The full program in .pdf format is here