From the searcher perspective, here are several general knowledge directories that focus on quality of content vs. the amount of entries. Each also has a written collection development statement. 

http://www.intutue.ac.uk

http://www.infomine.ucr.edu

http://www.lii.org

http://www.ipl.org

http://www.academicinfo.net

... and the reason that it doesn't rank is that the ODP added a set of site-wide 301 redirects from dmoz.(org¦com) and from www.dmoz.com all pointing to www.dmoz.org just a few weeks ago.

I expect things to be in turmoil until Google completely recalculates PR and backlinks.  I already see some interesting effects, and some patterns, here and there.

 The OP says "banned".  I say not. This is not a ban, merely a recalculation which will probably take a while.  

definitely not banned, and you were beaten by 2 hours in this thread..

 http://sphinn.com/story/6594

 I want my dupe button!!! 

Check the search strings posted in the other Sphinn thread for the answer.       

It is a very simple domain canonicalisation and Duplicate Content problem.      

Vanessa Fox mentioned these issues about another site only yesterday, too.