Okay this just got very weird. From one side I'm happy since it seems that main characters are the parents and the future lovers, but on the other hand I'm finding it rather odd that Hinata is the only one of the rookies that isn't mentioned. I don't want her to be a main character but I at least expected her to have some lines in the movie. The fact that Hinata is exclusively left out is something I find rather strange, specially since she was part of the first promotional poster while Neji, Sai, Rock Lee and Tenten weren't and yet they are listed as appearing.
My guess is that she was skipped accidentally from that list. And to be honest, I'm kinda looking forward to seeing Hinata act outgoing and seductive in this movie since it'd be so out of character from what we've seen of her in the last decade. Everyone would probably crack up at her scenes.
BRING ME SUPER SEXY HINATA TIME!

Well, you got to remember, the first poster is most likely a indication of what the movie is going to be about or the setting. Having Hinata unzipped shirt signaled the fans that something is "odd", which is most likely the genjutsu world. Teaser poster is there to tease and it's up to fans to guess. Team Gai is somewhat hard to tell the difference if they go opposite. Well then again, Neji can be all Lee-like

. So yeah, that was the purpose. I have a feeling Kakashi might be Gai level of crazy (judging him by going "super saiyan"

)
Don't worry about her showing up sexy. Like I said, I do believe her scene will be like a funny moment when Naruto and Sakura see her act all wild.