Gleen Greenwald does an excellent job of explaining why this report has little credibility. In summary, the report's main authors are people who supported the Iraq misadventure, and who in many cases have never publicly repudiated that initial support, despite the visibly sub-optimal outcome to date (I can circumlocute my language with the best of them). Russ Feingold's point stands: if you want a visionary outcome for an excercise like this, you don't exclude people who held contrary views at the beginning. As Greenwald explains, James Baker, one of the key members of the group, was a firm supporter of the invasion of Iraq, and has never publicly recanted his support.
This report is an excellent example of how to change strategy without introducing any element of public accountability for the bad decisions and strategies which led directly to the current poor situation in Iraq. In my day job in Information Technology, I refer to this as the N.O.Body syndrome - whenever something goes badly wrong, it is always nobody's fault - the problem seemed to miraculously occur without any human involvement or cause. N.O.Body is suddenly a member of the project or leadership team, so that blame can be assigned to a non-existent person.
What I find more disheartening is that the media seems to be unable to understand the lack of accountability, instead focussing on the "new beginning" meme. This is part of a broader accountability failure involving political leaders and the mainstream media, which is dotted with people whose opinions on the necessity and viability of invading Iraq have been shown in many cases to be absolutely wrong, but who are currently unable or unwilling to admit to having been misguided. In short, the political leadership and the media are collectively trying to sweep a lot of issues under the carpet, hoping that the "collective amnesia" approach will allow the whole Iraq mess to be finessed off the front pages of the news over time.