Hello, we used to rank top 3 positions for our 2 main keywords and since last 2 weeks we went to position 8 and 16 respectively.
Looking in WMT i found that there are many links coming from various sites (that do look spammy) that they actually show the ODP listings. We have never submit to these sites, as far as i can tell they are just reproducing the ODP directory.
I am also experiencing this. I have had a fairly significant drop in rank for my homepage that doesn't seem to tie in with any major Google update. Furthermore it is only my homepage that his been affected, for specific terms. Most of my natural links do not flow to my homepage but go to specific articles on my site. I have noticed an ever increasing number of these spammy ODP-copycat links. These actually make up a large portion of links to my homepage. Disavowing these or requesting removal from the DMOZ(radical I know) has crossed my mind.