This is an unmitigated disaster of a pick.
First, she's a Bush friend and that speaks badly of an administration constantly accused of excessive cronyism.
Second, she has no record as a conservative. At least a top legal mind off the bench with a track record of conservative legal thought would appease the base such that the Right would feel secure it is getting one of its own on the bench. People who know her (The Monk works with some of her former colleagues) say she is a moderate, at best. Her past political contributions include money to Al Gore and Lloyd Bentsen (both 1988). I'd discount her moderate contributions to Republicans in Texas in recent years because Dallas is a Republican county -- "Democrats" switch parties to get elected.
Third, she's a token not a representative of the excellent ranks of female jurists (Brown, Owen, Jones, Batchelder) or legal thinkers (e.g., Lillian BeVier) in this country. As Ramesh Ponnuru notes:
It's an inspiring testament to the diversity of the president's cronies. Wearing heels is not an impediment to being a presidential crony in this administration! I can only assume that the president felt that his support was slipping in this important bloc, and he had to do something to shore it up.
Fourth, she's a manager, not a top lawyer. Unlike Roberts, Miers has been outside the trenches for more than a decade. She was the managing partner of Locke Purnell Rain Harrell in Dallas (which had begun its downslide before she took the reins) and arranged its merger with the smaller but more competitive Liddell Sapp Zivley Hill & LaBoon into the larger Texas firm Locke Liddell & Sapp, of which she became co-managing partner. LLS is now dominated by the Liddell Sapp side and has been ever since she left for Washington.
Finally, this is a missed opportunity: the chance to really put a conservative stamp on the Court, re-assert the primacy of the President in the nominations process and shift the Court to the right after its unseemly drift to the left in the past three or four years.
For some reason, each Republican President since World War II has had the uncanny ability to appoint a stealth liberal (or two) to the Supreme Court. That's the Republican Quota. Eisenhower appointed Chief Justice Warren and Justice Brennan, men whom he later called his two worst mistakes of his presidency (The Monk has great respect for Brennan despite innumerable disagreements). Nixon appointed Blackmun who became the embodiment of weepy liberalism. Ford appointed Stevens, who was not particularly conservative at any point, is hostile to free speech and has long since gone off the deep end. Reagan appointed Kennedy, who looks to foreign laws to justify supporting liberal policies as constitutional rights. Bush pere appointed Souter. Bush fils has now appointed Miers.
Michelle Malkin parallels Harriet Miers to the unqualified Julie Myers -- the Homeland Security nominee.
Mark Levin sums the nomination up very well:
The president and his advisors missed a truly historic opportunity to communicate with the American people about their government, the role of all three branches of the federal system, and the proper function of the judiciary. More importantly, they have failed to help the nation return to the equipoise of our constitutional system. And the current justices whose arrogance knows no bounds will be emboldened by this selection. They will see it as affirmation of their "extra-constitutionalism." The president flinched. Some have compared have compared profligate spending to Franklin Roosevelt's New Deal. But no one will accuse him of FDR's boldness when it comes to the Supreme Court.
If people are disappointed, they have every reason to be.