Copy the unzipped epub.qlgenerator file into /Library/QuickLook
(for all users) or ~/Library/QuickLook
(for the current user only).
Copy the unzipped epub.mdimporter file into /Library/Spotlight
(for all users) or ~/Library/Spotlight
(for the current user only).
V1.8 pulls in a in a bunch of under-the-hood updates from @MaddTheSane.
Added BSD license.