When you rename a keyword, it doesn't change the name of the keyword on photos that have previously been assigned the keyword.

For example, as Adobe Bridge is right now, if I created a keyword "keyword1" and assigned it to 100 photos, then changed my mind and decided I wanted the keyword to be called "keywordA", I'd go to rename it and the 100 photos still have the tag "keyword1" and I have to go back and change them all to "keywordA". It should automatically assign "keywordA" to those photos previously assigned "keyword1".