The yahoo directory gives an authoritative link. Better impact in the serps. Dmoz copycats give more backlinks but not as much umpfff for the links gotten.
For all my domains I write the URL out on small piece of paper, place them in a bottle and toss them into the ocean. I find this to be a far more effective method of advertising than submitting to DMOZ. I hear that carry pigeons work better too, although I haven't been able to catch one yet to try it.
This thread is 2 yrs old. All you have to do is click on the 'suggest' site in the most suitable category for your site - thats all you can do!