1. DoubtAt Walter Kerr Theatre, 219 W. 48th St., nr. Broadway; 212-239-6200Eileen Atkins (Cold Mountain, The Hours) is replacing Cherry Jones as the spitting-mad Sister Aloysius, and Ron Eldard (Freedomland, House of Sand and Fog) replaces Brían F. O’Byrne as Father Flynn.2. SpamalotAt Shubert Theatre, 225 W. 44th St., nr. Broadway; 212-239-6200Simon Russell Beale, who’s been called the greatest stage actor at work today, replaces Tim Curry as King Arthur, and Lauren Kennedy (Les Misérables) steps in as the Lady of the Lake (replacing Sara Ramirez, who won a Tony in the role) .3. Dirty Rotten ScoundrelsAt Imperial Theatre, 249 W. 45th St., nr. Broadway; 212-239-6200Jonathan Pryce (Glengarry Glen Ross and both Pirates of the Caribbeans) replaces John Lithgow as the conniving smoothy Lawrence Jameson.