It's a great idea. The challenge with adding Keyword Destination URL as a classification being sent back into Analytics is that it is a dynamic attribute that can change at any moment -- whereas with Ad Destination URL there is an explicit 1-to-1 relationship between the ad ID and the destination URL (if you change the URL, you are actually deleting the old ad and creating a new one with a new ID). Not saying it's absolutely impossible, but because any user can change a keyword URL at any point ...

This functionality (along with all other paid and organic metrics viewable side-by-side) now exists in SearchCenter.

For those customers that have SearchCenter, the organic search query, the paid search query, and the paid search keyword (tracking code) are now all stored in their own eVars so they can use either first or last allocation, they can have their cookie expiration extended beyond the visit, and they can be classified to your heart's content.