This has been a great discussion, I have been lurking for a few days.
I am a DMOZ supporter and a new editor. I thought I would share some experiences.
I have been using dmoz for years. I signed up for chefmoz because I was holidaying in an area with no resturants listed. I decided I would eat out every day and list all the places I found and then add a few reviews. I got me thinking that I should sign up for dmoz and give a bit back. I had beening thinking about it for a while. So I applied about two months ago. The area I applied, and was accepted as an editor, was my work speciality. I do look after our company websites which could be listed in my dmoz area. I had submitted one of our sites and after 12 months it had not listed. I will admit there was a motive as an editor I could add the work website. But the bigger motive was getting the category right. It did not properly reflect the industry and had a mish mash of websites. I think if I got it organised with new sub-categories and better sites it would be a real valuable resource for the general public and the industry. So I really went into it with grand ideals etc.
I have worked with computers for over 10 years and I know my way around. But the first day I logged into dmoz I was lost. I clicked and poked around. It took a while to get use to it. The editors forum seems to have thousands of posts a day. I read all the rules and policies, but I didn't know where to start.
It seems that no one had edited my category for about 2 years. There were nearly 300 new submissions, and many sites sent by other editors.
To me, it seems dmoz (as an entity) wants to add as many sites as possible that has unique content. And that is the mantra - unique content. But as a new editor - do I delete the ones I do not want or do they go into unreviewed until later? My top editors didn't respond to my emails. I searched the forums and decided every editor has their own method and style.
My lofty ideals about making a great category resource started to rust as I realised the task set before me. 300 sites does not seem much but it is mind numbing. Most turned out to be dmoz spam or inappropriate (right off topic).
So this is how I spend my dmoz time.
I log in. Go straight to unreviewed. First site comes up. The submitted sites are in alphabetical order, I can not find how to put them in submitted order. If you have a site called "zzzzz time" this could be why your submission is being delayed - its the last one to be reviewed.
First site comes up and it is a summary. Who submitted, ip address, email address, title, description, any previous edits and any categories the site is already in. The dmoz system also has flags. Flags are notes that tell you if the site is spam, duplicate, recently expired or any note by another editor. So all those people buying expired domains that might have a dmoz entry - forget it - an editor would have to be blind to miss it. If it has expired and registered, dmoz system gives you options to search the whois etc.
So my first site review - I check dmoz and google for duplicate entries. I check the whois to see who owns the domain (a good way to find duplicates). I then go the the website to see what it is like. For me the things that rejects a submission is dupication (already in dmoz), deep (submitted link is deep link into site), inappropriate (non-english site or off topic), nothing unique. And the last one is the hard one. Nothing unique. And that seems to be a dmoz mantra - repeated again and again. And for a purpose: it helps with the editing. If the website is a reseller and is using someone elses database of parts - why listed it? The only thing unique is the domain name and to the owner/webmaster this is good enough reason to be listed. I have added resellers sites if they offer something unique - like a good faq, or new facts or info, forums etc. I think a lot of people forget when they submit you are asking for a human to review your website - it is a form of criticism. It is subjective. It is not perfect. It might not fit into the editors lofty ideals. We submit because it is in the webmasters handbook under how to make your site popular. It should be under - what your peers really think about your site. :-)
So I delete the submission because it is an affliate site with nothing unique - I have to type a reason and that is what I type. If I added a site - I also type the reason to help the next editor when I combust from monitor radiation.
If it is inappropriate I refer it to the appropriate category - which takes time.
Of the 300 submissions I have ploughed through, 60% were spam, 30% inappropriate, 5% maybes, and 5% approved. I added about 15 sites. My mind is numb. Some days I would walk away because the spam made me so angry or I could not tell if it was a good or bad site. Submit spammers are getting so clever - they hide the redirects, change the layouts but they just keep submitting. Not only is it taking more time to weed them out but it jades the editor, I know it does for me.
300 submissions took about 6 weeks, probably 75 hours work. And my category is a very minor, uncompetive one. I say a prayer at night for all those dmoz editors in a busy category.

I understand all the dmoz criticism and some of it is rightly placed. I think it is micro criticism and sweating the small stuff. No system is without flaws but the dmoz project should be looked at as a whole. Some categories are biased, understaffed, poorly edited. However as a whole, the good out weighs the bad and it is a good representation of the internet.