UPDATE:
John Hawkins has a list of reactions from the right side of the blogosphere.

UPDATE 2: Hawkins has more- reactions from the blogs on the left.

at the DU:
“They” (meaning Republicans) want all women to die. Pregnant.

It could have been much worse.

Roberts wants to overturn Roe V Wade.

Bush has a new facial tic. Maybe he’s hooked on crack! [Update: by the way, as Michele Malkin notes- the reason behind the weird expression had more to do with a restless toddler, and less to do with illegal substances. =oD]

We’re doomed. This guy is filibuster proof.

Bush’s evil plan is working. He only nominated Roberts to distract us from Rove. Don’t let him.

Says NARAL (National Abortion Rights Action League):
Roberts wants to overturn Roe v Wade

Senator Durbin (via Larry King Live)

“The next Supreme Court justice will make decisions that will affect the lives of millions of Americans for years to come. Even if a Supreme Court nominee is honest and professionally competent, that person must also be committed to protecting the rights and liberties that are at the core of our democracy.�

“The President had an opportunity to unite the country with his Supreme Court nomination, to nominate an individual in the image of Justice Sandra Day O’Connor. Instead, by putting forward John Roberts’ name, President Bush has chosen a more controversial nominee and guaranteed a more controversial confirmation process.â€?

“Now the Judiciary Committee will begin its work. For my part, I will look for one thing — will this nominee strive to protect the rights of all Americans or will he be a judicial activist with an ideological agenda rather than an independent judge with an open mind.â€?

Senator Harry Reid (statement):

STATEMENT OF SENATOR HARRY REID ON THE NOMINATION OF JOHN ROBERTS TO THE U.S. SUPREME COURT

The President has made his choice. Now the Senate will do its job of deciding whether to confirm John Roberts to a lifetime seat on the Supreme Court.

The President has chosen someone with suitable legal credentials, but that is not the end of our inquiry. The Senate must review Judge Roberts¹s record to determine if he has a demonstrated commitment to the core American values of freedom, equality and fairness. The nominee will have an opportunity to testify before the Senate Judiciary Committee and make his case to the American people.

I will not pre-judge this nomination. I look forward to learning more about Judge Roberts.

People For the American Way (PFAW )

“It is extremely disappointing that the President did not choose a consensus nominee in the mold of Sandra Day O’Connor,� said Neas. “John Roberts’ record raises serious concerns and questions about where he stands on crucial legal and constitutional issues – it will be critical for Senators and the American people to get answers to those questions. Replacing O’Connor with someone who is not committed to upholding Americans’ rights, liberties, and legal protections would be a constitutional catastrophe.�

They’ve also provided a handy dandy pdf file containing a “preliminary report” on Roberts here.
Overview of the report:

Roberts’s record is a disturbing one. Among other things,
Roberts is hostile to women’s reproductive freedom, and he has
taken positions in religious liberty and free speech cases that
were detrimental to those fundamental rights. Roberts has
limited judicial experience, but even his short tenure as a judge
raises serious concerns about his ideology and judicial
philosophy. For example, dissenting opinions by Roberts have
questioned the constitutionality of the Endangered Species Act
and argued that Americans tortured by Iraq when it was a
terrorist state can receive no compensation. This preliminary
review of Roberts’s record indicates that it falls far short of
demonstrating the commitment to fundamental civil and
constitutional rights that should be shown by a Supreme Court
nominee.

The DKos has a “dkosopedia” listing on Roberts here.

AP quotes from both sides regarding the nomination here.

Senator Charles Schumer (via CNN- Larry King)

There’s no question that Judge Roberts has outstanding legal credentials and an appropriate legal temperament and demeanor. But his actual judicial record is limited to only two years on the D.C. Circuit Court.

For the rest of his career, he has been arguing cases an as able lawyer for others, leaving many of his personal views unknown.

For these reasons, it is vital that Judge Roberts answer a wide range of questions openly, honestly and fully in the coming months.

His views will affect a generation of Americans, and it his obligation during the nomination process to let the American people know those views.

The burden is on a nominee to the Supreme Court to prove that he is worthy, not on the Senate to prove that he is unworthy.

I voted against Judge Roberts for the D.C. Court of Appeals because he didn’t answer questions fully and openly when he appeared before the committee.

Senator Boxer (statement)

“Without prejudging the nominee, I do believe Judge Roberts’ record raises questions about his commitment to the right to privacy, protection of the environment, and other important issues.

“With so many rights of the American people hanging in the balance, this Supreme Court nomination deserves a thorough and in-depth evaluation.

“Justice Sandra Day O’Connor’s replacement could take one of two paths: Judge Roberts could go down the same independent, non-ideological road as Justice O’Connor, or he could join with the right-wing block on the Court which has consistently expressed the belief that a woman’s right to choose isn’t guaranteed, nor is the federal government’s ability to protect workers, the environment, and a family-friendly workplace.

“I look forward to the in-depth hearings by the Judiciary Committee and a further evaluation of this nominee.”