You can also try Rockbox, wich will probably go much faster (and allow you to update while playing music). I don’t own a Clip ZIp, but I’ve always found the database software on the Fuzev2 and the Fuze plus to be quite slow. Rockbox’s db, on the other hand, takes only a minute or two, where the stock firmware can take four or five. Plus, with Rockbox, you don’t actually need a db, and can just browse by file if you so desire.
On the down side, Rockbox’s interface (especially the menus) isn’t as nice as the stock firmware. Also, the Rockbox website lists the Clip Zip as “unstable”, meaning that there may be a few minor bugs with this particular device, but the Clip Zip wiki states it as being “fine for day-to-day audio playback”.