Fantastic animation, wonderful story, jokes thrown in that adults will get but, of course, fun for kids too plus a voice actor cast that is perfectly cast. You'll also love the nods to some classic scenes in past movies such as the "Twilight Zone" airplane scene and the Indy Jones' heart removal scene done on a gummy bear (I'm not making this up).
The script is beyond great and Bill Hader has perfect comic pacing as the lead.
The underlying social commentary on how many Americans crave total junk as their diet is unsubtle but still it works. In a way the movie works on many levels so I'm sure with repeated viewings you'll get even more out of it.
All in all, there were so many burst-out loud laughs and little chuckles at even the throwaway lines or scenes, that it truly is one of the best comedies of the year.