Janet Jackson is down with some kind of toxic flu, so Mariah Carey is stepping in for the pop star to perform on Saturday Night Live this weekend. This is really only news if Mariah manages to develop a sense of humor in the next 48 hours and parodies herself in an SNL skit. Mariah as a mentor on American Idol? Mariah in a crazy diva-off with Celine Dion? The possibilities are limitless. We're not counting on it, but we'll set our DVRs just in case!