I found some more relevant and fun blogs on the net, links to which have been added to the sidebar. First there's Opinio Juris, dedicated to "reports, commentary, and debate on current developments and scholarship in the fields of international law and politics". A second Blog I can recommend enthusiastically (for one: because not only dedicated to, but also set-up from a comparative perspective) is the aptly called Transatlantic Assembly. Here you should find materials on "European and American Constitutional Law (with an eye to the European Constitution), International Law, European Law, Law and Philosophy", posted by European and American academics and practitioners. Finally, you could have a look at the Weblog maintained by the American Constitution Society for Law and Policy (ACS) for information and comments on American constitutional affairs. Happy blogging!