This is a simple idea for enhancing tagging functionality in WordPress with the Simple Tagging Plugin (or any other tagging plugin). Basically the user would setup word/phrase to tag/tags associations and any time the word/phrase was found in a post that post would automatically get tagged with the associated tag/tags.
For example I might setup an association like "WordPress" = "wordpress,blogging software". So now anytime I write a post containing the word WordPress that post automatically gets tagged with the tags "wordpress" and "blogging software".
Basically once it was setup correctly tagging would require no extra effort at all and it would be very consistent. Unfortunately I am not experienced enough to code this myself but if anyone would like to take it on I will be happy to beta test and consult on the project with you.