All indications are that Acting Solicitor General Neal Katyal will argue the case on behalf of the United States, a rather extraordinary occurrence in the court of appeals. (Katyal just argued last Tuesday on behalf of the government in American Electric Power Co. v. Connecticut, the huge global warming-public nuisance case up on cert from the Second Circuit.)
Under a recently adopted Fourth Circuit policy, MP3 audio files of the arguments will be available within 48 hours after the arguments. But they might be posted sooner. Here is precisely what the Fourth Circuit's web site states:
Effective with the May 2011 argument session, links to Fourth Circuit oral argument audio files in MP3 format will be posted two days following argument. Audio files for high profile cases may be posted earlier.From what I understand, the Fourth Circuit will be deciding in the next few days whether it plans to release the audio earlier than next Thursday--perhaps as early as Tuesday afternoon. (If anyone hears, please let me know.)
And again, we will not know the identity of the three judges sitting on the panel until Tuesday morning.