The always superuseful ScotusBlog says, cool it already on any premature speculations on who the retiring Justice Souter's successor might be:
…people will talk about a "short list." They have no idea what they are talking about. There presumably is a fluid working list of possible candidates at the White House. But it no doubt changes, and only a handful of people even in that building would know who is on it at any given time. The "short list" is a dressed up way of saying "conventional wisdom."
Third, no one knows whether the conventional wisdom is actually sound because it depends on a threshold question: what is the President looking for in terms of vision, ideology, and background. You can take it as a given that the President wants someone incredibly smart and qualified, and with perfect integrity. And a woman. And someone younger than 60. But what about the candidate's past experience—in politics, in judging, in academia? What about their ability to lead?….President Obama is going to face trade-offs, and if people tell you that they know what qualities he is going to value more than others, they likely are just making it up.
Still, even he can't resist the naming names game:
My bet is that—this early on—it's a big and diverse list. It would have some very well known judges (for example, Diane Wood and Sonia Sotomayor), academics (Elena Kagan (now Solicitor General), Pam Karlan, and Kathleen Sullivan), and politicians (Jennifer Granholm, Amy Klobuchar, Claire McCaskill, and Janet Napolitano).
As Roland Hedley used to say, only time will tell.