If Mai's reaction to Uta hadn't already won me over, that little sneaky grin she threw at the camera as it panned by, in response to there being Kenshuusei, definitely would have.
^It's not just about promotion. Satoda said that she chose Momoko because she's graduated from university while being a busy idol and talent, that she has a good head on her shoulders. This is a member who has 10+ years experience as an idol and plenty to teach the new kids, someone who knows how hard it is to be an idol and a student, and someone who knows how to get exposure. Obviously, she's also a great asset for promoting them on TV, but it's more than just that.