I got a chance to play with the new version (not yet released) of the Cricut Design Studio that works with Vista 64 and I found 2 new features. Below is a picture of one of the features. You can open a .cut file and then under 'Cricut Cartridge Library' you can use the pull down menu and click on 'This Project' and the software will display all the cartridges used on this .cut file. Cool huh.
(You can click on the picture to make it larger, makes it easier to see the image.)