A lot of more Conservative commentators are calling for the captured terrorist to be declared an 'Enemy combatant' and tried by military tribunal, even though he was lawfully in the US and committed his crime within the territorial jurisdiction of the US. Personally I think it's a bad idea, since it crosses a line where the Bill of Rights won't apply to an accused if the person who happens to be President at that time decides the accused was consorting with or supporting the wrong people by the ruling party's own political lights, and anyone else associated with those 'Wrong people' ever committed an act of violence (The facts are a lot more clear cut with the bomber now in hand, of course but once the principle of BOR protection is knocked down for one guy, there isn't any legal control on how far it can go as long as the label 'Terrorist' gets slapped on an act or an entire group by the Prez).
There is also some logical flakiness to the application of the whole 'Miranda exception' in this case, since there is no particular reason to believe there is a ticking bomb or activated confederate on the loose, really a different but related topic. While I'm on it, though, it's just my personal educated opinion on that one that if the little bastard survives and goes to trial, the government will ultimately end up defending that part of their case at the Supreme Court, with less than an even chance of winning the point (Though it appears there is far more than enough evidence to convict his ass even if he did lawyer up, which makes the need to resort to such an exception pretty questionable in the first place, and anything he could tell them about associates is almost certainly obtainable from his electronic and paper footprint). The Miranda exception does not prevent an accused from lawyering up or zipping his lip, by the way, it just means the prosecution can still admit into evidence any statement made before the accused-in-custody was read his 5th and 6th Amendment rights.