Design [ 85% ]
When we think about archive sites we have to know that the easy of browsing is much more important than killer graphics with heavy load images. ADND.com is amazingly visited and they were wise by making a rapid loading site. Tough the logo and backgrounds could be better, its surely satisfactory for one who enter there looking just for D&D posts.
But there are still some flaws at the browseability: Such as the spells which aren't listed by spell levels but by names and... Well, actually I found just these :o) By the way, their internal search engine, devised by sections, is very precise.

Content [ 85% ]
Ok, there are really many many posts at ADND.com, but don't get too much impressed by that, since actually a huge amount of them aren't that good, and that's precisely the major problem of the site... Take a look at the Races by example, there are some posts who describe a race with one or two paragraphs! Not to say that some are totally out of rule.
Still, there are many posts, and since its all easy to browse by, you will find adequate ones with some time. Particularly at areas like Rules, Netbooks and even Humor (some posts here are more serious than the non-humorous ones). But lets suggest something: There could be a basic form for each posting. Like "Race. Description, Appearance, Culture/History, Abilities, Magical Powers, etc..."; That way people who send stuff would be more inclined to perhaps write a little bit more...

Originality [ 85% ]
To have a rating here we have to take a peak at the middle level of the posts. And after all they are quite original sometimes, and just mere copies other times... But the whole site is original since it was one of the first archive sites of D&D who asked for visitors contributions.
Other than that, it hosts some great netbooks and some original sections like the Humor. Perhaps you could subscribe to be a member and chat with the other visitors too, that way you can say by yourself if its that original or not. I had to give a rating, and for the most part of the site, I think its a fair one.

Hot Spot [ Netbooks, Humor ]
Weak Spot [ Weak posts, particularly at Races ]
Total [ 85% ]