Perhaps you are confusing DMOZ/ODP (www.dmoz.org) with TOD (www.theopendirectory.com)? TOD is using a blue colorway, but is not related to the ODP, DMOZ, or Resource-Zone in anyway other than mimicing DMOZ in apperance and using ODP data as far as I know.
I think he means the "Reply" "Quote" "Edit" "NewReply" buttons on postings and the little blue folders in the forum "tree" at the top of the thread pages, and the bluetone icons for "new messages" or "no new messages" on the main forum page.
Ah. I can't imagine going to the trouble to change out those buttons. They look fine with the few skins that we are using here. I thought about installing a few more style packs, but I couldn't really see a good reason for doing it. Just adds more things that could potentially break
Are those buttons always blue? I can't remember, I changed my color scheme months ago to blue vs green and they look pretty good to me. I thought they were very professional vs amateur.