The difference between tribunals and courts-martials:

The central question is what kind of forum to set up. Commissions allow the government wide berth in introducing evidence, including hearsay, which is banned in military courts, and restrict the rights of the accused to be present in the court and to see the evidence against them. Military courts-martial, while not as strict as civilian courts, restrict the kind of evidence that can be introduced and allow the accused to interview witnesses and see even classified evidence.

Options: From John Yoo, one of the primary drafters of the infamous torture memo :

"The debate that people are having is whether it's going to be a short bill that just overrules Hamdan completely, which you could do in one sentence, or whether it's going to be a much more comprehensive law that tries to set out essentially a code of procedure for the military commission."

Sen. Patrick Leahy:

"The Supreme Court said the president cannot continue to break the law," said Mr. Leahy, the Vermont Democrat. "The worst thing to do would be to simply paper that over and say we'll make it possible for him to break the law."

Should make for interesting hearings. Also see Christy at Firedoglake who reports on the ethics dust-up going on with Sens. Graham and Kyl over mispresenting (fabricating) a portion of the Congressional record in their amicus brief in the Hamdan case. More info on this is available in John Dean's latest column at Findlaw. Background from Emily Brazleton at Slate is here.