That sounds like a good idea. Just to bad that firef***s crashes now and then. Mine was crashing two times while I was writing this reply. Directory submission is still cool as long as it yields a couple of backlinks. Since directory owners are lazy it takes time to get listed, but then this distributes the link registration on google also over a natural amount of time.
If your site is about software products also see RoboSoft for automatic and semi-automatic submission.
For those of you who only do manual submissions, you have never tried digixmas. If you set it up right, the titles and descriptions are all randomized using tokens (variables) defined by you. When done manually, you repeat the same information to often. Furthermore, with digixmas you still have to select the proper category, it just gets smarter as you make more submissions. It remembers what categories you have chosen in the past and narrows down your selections. This makes picking the right category even more accurate than doing it manually.