Carol Ebbinghouse, The New Surge of Open Legal Information on the Internet, Searcher, June 2008. The article itself is not online, but here's the online blurb for it in the table of contents:
Carol Ebbinghouse compares the quality of legal information now available for free on the internet to the old, reliable, and fee-based services such as LexisNexis and Westlaw and discusses how these new resources can both help and hinder users.
Posted by
Peter Suber at 6/01/2008 02:51:00 PM.
The open access movement:
Putting peer-reviewed scientific and scholarly literature
on the internet. Making it available free of charge and
free of most copyright and licensing restrictions.
Removing the barriers to serious research.
I recommend the OA tracking project (OATP) as the best way to stay on top of new OA developments. You can read the OATP feed on a blog-like web page or subscribe to it by RSS, email, or Twitter. You can also help build the feed by tagging new developments you encounter.