A member's 2ch thread is usually the easiest source of information, but you have to often wade through some degeneracy (and it's all in Japanese of course). They do a good job of keeping you updated on what kind of appearances a girl will make and whatnot.
As for popularity, she's popular enough to be in the NMB48 senbatsu, even though I don't think she's quite popular enough to be guaranteed her senbatsu spot in the way she has compared with the handshake numbers for girls like Airi, Kanakichi, Keila, Uuka, Shimarena. She didn't really move the needle a whole lot when she was put into AKB48, but management really likes her and she does stand out due to her personality on screen, so I wouldn't be worried about a lack of opportunities. I think I would be surprised if she made it into the elections next year though.
. Someone nicely translated her message: 
