As promised, here is a small beta release focusing squarely on localization fixes. We got these changes too close to the release of OmniGraffle 5.0.1, so here they are in their own release.
Quite a number of fixes to the Japanese Help and User Interface have been made, and we've amended the “Paste and Match Style” string to reflect the iWork apps in German.
Since there's no code changes from OmniGraffle 5.0.1, there's no rush to download this beta unless you have an interest in the Japanese localization, on the other hand, code-wise it's the same as 5.0.1. (more or less)
As ever, the beta page awaits!