Well that was quick. First Mail.app received a widescreen, three-pane face-lift, and now it's been morphed into a plug-in. The author provides two different sets of instructions for installing: drag and dropping into your ~/Library/Mail/Bundles/ directory or using a couple of commands in Terminal. Go nuts ladies and gentlmen.

This article was originally published on Tuaw.
RapidWeaver 3.5