theedge.bostonherald.com and toronto.fashion-monitor.com:

The film festival rumor mill is working overtime with the notion that Tom Cruise will make a surprise appearance at the Cannes Film Festival Wednesday to promote his new flick “War of the Worlds.”
Word is that Cruise, who is scheduled to show at the nearby Monte Carlos Grand Prix next week, will show up on the Croisette, the beachfront promenade, to pose under the mammoth “War of the Worlds” poster at the Carlton Hotel. With a captive audience of 4,000 journalists, Cruise knows that Cannes is, in the words of producer Joel Silver, the world’s stage for l0 days.
Whether Cruise will show with his new arm candy Katie Holmes is another question.
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And Tom and Katie went to a gala at Santa Barbara hosted by Oprah Winfrey to pay tribute to pioneering black women, according to centredaily.com