Yes it will help IF you ever get approved. I have been waiting 2+ years with one site, so don't hold your breath or you'll pass out or die.
Sorry to say this BUt i didnt help me. I got approved in less than 6 months. DMOZ even paid a visit once a while just to make sure im still on the topic im listed on. But over all, no difference at all. Google just dont care any more. Its just one link from a pr8 site that have like a million link going out.
Of course, it's not enough to rank right away #1 in SERPs, but in a linking strategy, a link from a dmoz's PR8 page, help.
It didn't help for serp or traffic. I have my site listed for a long time and I never apply by myself so. Sorry to say this too.