I was a longtime fan of the free Keyword Assistant program, so the developers of Keyword Manager had a high hurdle to overcome to convince me to go from a free product that I liked to a shareware product.

Well, I'm a registered user now. This program has such a fast and easy interface that it makes adding keywords to your photos fun.

Highly recommended if you have a lot of photos. Two things impressed me in particular:

1) If you change your keyword structure the keywords already assigned to your photos change to reflect the new structure.

2) The ability to copy and paste keywords from one photo to another. Big timesaver.

I only gave the program a 4 for features because I can see some logical areas for it to gain more abilities.

For example, it could offer the ability to embed your keywords into the photos themselves (I don't think iPhoto does that currently).

But overall this program gets a 5 star rating from me.