A couple of important things to talk about in this release, aside from various bug fixes (which are faithfully documented in the historical release notes).
The first of which is, we've added multi-touch support for zooming the view, and resizing and rotating selections. If you've got one of the newer MacBooks that support multi-touch on the trackpad, a pinch will zoom the view in and out. If there's a selection, pinching will resize that selection, and you can also rotate said selection. Please let us know how this works out for you, we have a feeling that at present the multi-touch support is somewhat sensitive.
Secondly, we've added a hidden preference to persistently display the layer status icons in the Canvases Sidebar, to match behavior that was present in OmniGraffle 4. If you'd like to have these icons show all the time (as opposed to mouseover or in their “on” state), open up Terminal.app and paste in the following and press Return:
defaults write com.omnigroup.OmniGraffle AlwaysShowLayerStatusIcons YES
If you're running OmniGraffle Professional, the above should read as:
defaults write com.omnigroup.OmniGrafflePro AlwaysShowLayerStatusIcons YES
As always, the beta page awaits.