A show called Feedback on a site called G4 invited Double Fine CEO Tim Schafer and art director Lee Petty on the other day and the results can be seen right here.
The first 24 minutes of the video feature Schafer and Petty, and the four participants spend that time discussing various video game related things. That includes the upcoming Stacking, and they do not neglect to showcase some footage that may or may not clarify the degree to which this game converges with your notion of an adventure game, should that matter.
Source: G4TV.com