[JKT]

Oops, the plug-in is a third party development and they have a note on the website that they are working on compatibility with Keynote 3 (or '06 or whatever it is). However, no idea how long that note has been there as it isn't time stamped, and the official linkback page hasn't been updated in a long time either.

Anyway, getting OmniGraffle content into Keynote is still the same - copy and paste.