I used iPhoto 4 very happily, had 20K photos in a single library, like Apple wants, and had more than a hundred keywords to manage these. Then I got an intel Mac and iPhoto 6, which converted all my photos to the new incompatible format. The new keywords are very unsatisfactory. Whereas the old iPhoto had a single window pane in which you could add new keywords and apply them to selected photos, the new iPhoto has an extraordinarily clumsy procedure involving many windows and many mousings. It may be fine for a child with only a few photos, but it is totally useless for me.

Furthermore, on my intel dual core machine it takes 20 minutes to assign a keyword to one roll of 50 photos. The gurus at the apple store have no explanation, can only guess that I have too many photos or too many apps or have "third party" software somewhere on my hard drive.

I have gone back to iPhoto 4. It takes 2 seconds to apply a keyword, and works fine for me.