The Goldsmith-Katyal proposal for a "National Security Court" that could authorize preventative detention has provoked an extensive debate in the comments to this post at Opinio Juris. At Is That Legal? Eric Muller thinks the proposal "has a lot going for it," but is surprised that Goldsmith and Katyal would propose authorizing the preventative detention of U.S. citizens on the basis of simple group membership.
[NOTE: I revised this post so as to more accurately portray Eric Muller's thoughts on the GOldsmith-Katyal proposal.]
UPDATE: Amos Guiora expands on his domestic terror court proposal here.