Some people have translated the story form magazines, and people are saying that it reads "On the whole, the movie would “go back to square one” of the series, i.e. the relationship between Hayate and Nagi" and also the story article mentioned something about it being a “Milady is my life in itself (Sparkling!)” movie.
ALSO, the real story is that basically "It is the last days of summer vacation. As the new school term draws near, Nagi becomes more and more moody. In an effort to cheer her up, Nishizawa Ayumu (Hamster) invites her to come to her farm house in the country... The article mentioned one of Nagi or Hayate being in trouble (of course) and the two of them being seperated... Also, something was metioned about Maria wearing a new comstume of some sort, and as the looks of it, some people are saying Luca might be introduced...
All in all, you can expect a Hayate-Nagi love comedy of some sort (yay for me since I'm a Hayate x Nagi fan ^.^) Hope this helped, and yeah, this was a HUGE paragraph... lol.
(Everything about the story was directly translated from a magazine article, which you can see here:
http://doughnutgunsoshayatereport.fi...yatemovie2.jpg)