Capcom has been doing weekly streams on their Twitch channel, and today’s stream featured two hours of Monster Hunter Generations. The Story and Prowler Modes were the focus of the stream. Capcom is no longer streaming for the time being, but an archive of the entire stream can be found at the link below, if you wish to check it out for yourself.
Monster Hunter Generations will release in Europe and North America on Nintendo 3DS later this year.

does this game actually have a decent story mode? I struggle to stay interested in MH games due to lack of a real story
Sadly -for you- MH games have never been about the story, is about defeating monsters and making armor and ranking up, and the story is just a excuse to present the tutorial. This said… no, this game wont have a good story. Sorry.
Wait.. You can be a Palico?!