Copying Your Keyword List To Another Library

One of the key features of iPhoto Library Manager is that it will copy a photo's list of keywords when copying the photo from one library to another. However, this only helps for keywords that are actually assigned to one or more of your photos. What if you have a large list of keywords, but some of them aren't actually assigned to any photos in your library? How can you take that keyword list and duplicate it in another library? Here's one technique that utilizes this feature of iPhoto Library Manager:

Open the library whose keyword list you want to copy and choose a photo in the library. We'll call this our 'dummy' photo. You can even duplicate an existing photo to use as a temporary 'dummy' if you don't want to be modifying any of the existing photos.
Assign every keyword in the library to the dummy photo (or at least every keyword you want to bring over to the other library). Note that doing this through the keyword pane in the lower left is a big pain in the butt, since you have to draaaaag the photo on to each keyword over and over again. Try using the info window (command-i) which has simple checkboxes, much better for quickly assigning multiple keywords to a photo.
Copy that photo over to the library you want to copy the keyword list to. iPhoto Library Manager will copy the photo over, then assign all the keywords in the list to the copied photo, effectively recreating the whole keyword list in the destination library.
Now that the photo's been copied and the keywords recreated, you can delete the dummy photo from the destination library. You can also return to the original library and remove all the keywords from the dummy photo, or just delete it if you made a temporary photo for this purpose.

Another similar technique, if you create new libraries fairly often and like to have a standard list of keywords in your libraries, is to create an empty library and use this technique to populate its keyword list, then just keep it around. Whenever you need a new library, instead of creating a blank one, just use the "Duplicate Library" command to duplicate this library, along with the whole keyword list. Now all your new libraries will start out with the same custom keyword list.