I mean, sure, in hindsight Roberts in particular has turned out far more conservative than was predicted by most people, including Obama (and me, for that matter).  And a filibuster might have been a good idea (or not, if it game the republicans a stronger issue to run on in 2006).

From his statement on his vote on Roberts:

the decision with respect to Judge Roberts' nomination has not been an easy one for me to make....

I am sorely tempted to vote for Judge Roberts based on my study of his resume, his conduct during the hearings, and a conversation I had with him yesterday afternoon.

There is absolutely no doubt in my mind Judge Roberts is qualified to sit on the highest court in the land. Moreover, he seems to have the comportment and the temperament that makes for a good judge. He is humble, he is personally decent, and he appears to be respectful of different points of view. It is absolutely clear to me that Judge Roberts truly loves the law. ...

The problem I face ...is that while adherence to legal precedent and rules of statutory or constitutional construction will dispose of 95 percent of the cases that come before a court, so that both a Scalia and a Ginsburg will arrive at the same place most of the time on those 95 percent of the cases -- what matters on the Supreme Court is those 5 percent of cases that are truly difficult. In those cases, adherence to precedent and rules of construction and interpretation will only get you through the 25th mile of the marathon. That last mile can only be determined on the basis of one's deepest values, one's core concerns, one's broader perspectives on how the world works, and the depth and breadth of one's empathy.

...In those circumstances, your decisions about whether affirmative action is an appropriate response to the history of discrimination in this country or whether a general right of privacy encompasses a more specific right of women to control their reproductive decisions or whether the commerce clause empowers Congress to speak on those issues of broad national concern that may be only tangentially related to what is easily defined as interstate commerce, whether a person who is disabled has the right to be accommodated so they can work alongside those who are nondisabled -- in those difficult cases, the critical ingredient is supplied by what is in the judge's heart.

I talked to Judge Roberts about this. Judge Roberts confessed that, unlike maybe professional politicians, it is not easy for him to talk about his values and his deeper feelings. That is not how he is trained. He did say he doesn't like bullies and has always viewed the law as a way of evening out the playing field between the strong and the weak.

I was impressed with that statement because I view the law in much the same way. The problem I had is that when I examined Judge Roberts' record and history of public service, it is my personal estimation that he has far more often used his formidable skills on behalf of the strong in opposition to the weak. In his work in the White House and the Solicitor General's Office, he seemed to have consistently sided with those who were dismissive of efforts to eradicate the remnants of racial discrimination in our political process. In these same positions, he seemed dismissive of the concerns that it is harder to make it in this world and in this economy when you are a woman rather than a man.

I want to take Judge Roberts at his word that he doesn't like bullies and he sees the law and the Court as a means of evening the playing field between the strong and the weak. But given the gravity of the position to which he will undoubtedly ascend and the gravity of the decisions in which he will undoubtedly participate during his tenure on the Court, I ultimately have to give more weight to his deeds and the overarching political philosophy that he appears to have shared with those in power than to the assuring words that he provided me in our meeting....

So he basically said outright that he thought Roberts was dissembling. And like HRC he also voted no because of the WH's withholding of documents on Roberts' record that would give them more opportunity to make an informed judgment.

You can (and people do) parse him all over the shop.

What kind of judges would he pick? No idea.

I've heard people say so many times "that means x", or "he really means y". If that is the case, why won't he just say what he means?

I spent a good deal of time fighting against the Roberts nomination at daily kos, on the front page.

Their current legal commenter, Adam B was a HUGE defender of John Roberts.