Version 3 of the OmniGraffle Wireframe Stencils has been posted. Download it now.

Modified all form and controls elements for color consistency. Added the following: sliders, new form icons, tag clouds and lists, a-z lists, IAB advertising units, iphone chrome, web browser chrome. You'll also see the start of a style guide based on the UI components here, which is being used for the Prototyping Kit we're developing.