Currently Being ModeratedNov 11, 2012 5:04 PM (in response to Stephen Connor)
Looks like a bug in the latest version of Aperture. The exported keyword file name is missing the extension it should be .txt.
If you open a Finder window on the folder where the keyword file is that you exported and add a .txt. extension to it Aperture should see it as a keyword file it can import.iMac, OS X Mountain Lion, Aperture 3.4.1