Oh, good question: I'll add that to the FAQ and try to get some images posted.
Included stencils are:
- 3D - squares, rectangles, & various cube-like shapes, from an isomorphic perspective, plus a styled line to connect them appropriately.
- Connections - styled lines & connector shapes (a lightning bolt, for example)
- Fills - "color chits" to drag onto existing shapes and apply fills/text styling.
- Fonts - eponymous "font chits" to use as a shortcut for adding styled text. (Drag the "Futura" object, for example, and then edit the actual text you want to appear in that font face.)
- Shapes - 15 different 2D polygons, in both shadowed and un-shadowed variants.
- Software - the "Flowchart", "UML - General", "Entity Relationship", and "Garret IA" stencils from OmniGraffle for Mac.
- Variables - same variable options an OmniGraffle for Mac; looks like "X position" and "Y position" are the only ones not there from the Mac version.
Keep in mind that there are tons of free stencils available on Graffletopia, which should also work in the iPad app.