Glenn Greenwald, far and away the most professional and intellectually honest blogger I've ever encountered, has an excellent defense of the rule of law here.
Too many Obama supporters are willing to look the other way on this issue, since he came out in favor of the "compromise". McCain, of course, is far worse on this issue--his recent claim that allowing Guantanamo detainees habeas corpus rights was one of the worst Supreme Court decisions in history gives you a sense of where he stands. In short, I can understand why they would want to refrain from criticizing Obama, insofar as they fear it would weaken his electoral prospects and could result in something far worse.
But, as cynical as I may be about a lot of things, there are some principles which I believe should be upheld despite the political repercussions. The rule of law is first and foremost on this list. Early modern philosophers like Spinoza and Locke (who stole many of Spinoza's political ideas without citing him) recognized the corruptibility of humans in power, and sought to establish rules of governance to circumvent this corruption. (Even then this was not a new idea; political principles like the separation of powers can be traced at least as far back as the Roman Republic.)
The authors and advocates of the Declaration of Independence and the US Constitution, for all their imperfections, appreciated how vital the rule of law was for long-term stability and a just society. No human being, no matter how seemingly wise or benevolent, should be entrusted with the powers of a monarch. That includes Obama. (In fact, the only exception I would even consider is if such power was necessary to reinstate the rule of law because of a jaded and distracted populace who failed to recognize its importance.)
If any of this resonates with you, read Greenwald's article. It is well worth your time.