I've added a few links about which I'm very enthusiastic to the sidebar.
(The sidebar, incidentally, now temporarily follows a bad bad western-centric setup; this'll change in the near future, I promise)
SCOTUSBlog, maintained by the American lawfirm of Goldstein & Howe gives an extremely detailed overview of US Supreme Court affairs, including commentaries by the bloggers themselves and links to an impressive number of US media and academic commentaries that cover the Supreme Court. Highly recommended.
Balkinization is the weblog of several American law professors including Jack Balkin, Ian Ayres and Mark Tushnet. Great stuff (for a recent example, have a look at professor Tushnet's post on Tribe's Treatise on Constitutional law here).
Political Theory Daily Review offers updates and links on the widest selection of newsmedia and academic publications in the broad field of political theory (including many legal topics) of all the sites that I've come across. Very useful.