Maria Guleghina will perform a concert at the Mariinsky Theatre on the 5th of July 2010 and will sing arias that were chosen by the public. You can find more info and the official Vote Poll at the website of the Mariinsky Theatre:
International Public: http://www.mariinsky.ru/en/playbill/playbill/2010/7/5/2_1900/
Russian Public: http://www.mariinsky.ru/ru/playbill/playbill/2010/7/5/2_1900/