If you have the chance go. Their concerts are truly impressive. Per their website:
opening Fri 07 Jan 2011, closing Sat 08 Jan 2011
Slavic music expert Mark Bailey from Yale University returns with a program of native Slavic chants and extravagant Baroque motets for Christmastide. Written in as many as 12 parts, these “partesny” works (sung from partbooks) will feature music by Moscow’s most important Baroque composer, Vasily Titov, and two dramatic choir concertos written for St. Petersburg’s Imperial Court Chapel by its most celebrated director, Dmitri Bortniansky. The program will first take place on January 7 (December 25 in the Old Style, Julian calendar), the date of the Feast of the Nativity celebrated throughout the Slavic world.
2 hours with 1 intermission