Making his preferences known, Obama will be outed, as he reveals his Supreme Court nominee.  It will be hard to mask a hard to the left choice as representative, post-partisan or moderate.  His claims to the contrary will matter less and less as moderates loving Obama have to swallow their pride and admit that if it walks like a duck and quacks like a duck, it is a duck.

Ed Morrissey sees this nomination as a big head ache for Obama, changing the make-up of the Court little, but obliging Obama to satisfy demands in an open air arena.

He will face many competing pressures in selecting a replacement.  Supreme Court picks are high-profile affairs, and this will test Obama far more than his previous appointments — many of which have been disasters, like Tim Geithner, Tom Daschle, and the rest of the tax-evaders and lobbyists he’s picked.  Hispanics will want a representative voice on the court, and women will want to gain back the second seat that they lost with Sandra Day O’Connor’s retirement.  Blacks might expect Obama to appoint another African-American.  Meanwhile, in the Senate, Obama will be expected by some to play the bitter partisan game that has existed ever since Ted Kennedy kneecapped Robert Bork, and expected by others to pick someone in the middle ground to end those games. The biggest tension will come from the far-Left activists of Obama’s party.  They’re losing a stalwart.  They can’t afford to have Souter replaced by a middle-ground justice who may not vote as reliably liberal as Souter.  In fact, that will be Obama’s problem for all of the likely retirements on the Court — Ruth Bader Ginsburg and John Paul Stevens.

Michelle Malkins gives the down and dirty on likely nominees :