In the legal gossip world, (hell, even in the real world), a lot is currently being made of the fact that Supreme Court Justice John Paul Stevens has only hired one law clerk so far this term. In SCOTUS speak, this kind of dalliance in hiring help is often interpreted as an indication of probable retirement. Not that this was unexpected -- Stevens is 89 years old, which makes him the second oldest justice in history.
A friend reminds me that for a long time, there was a tradition that, when possible, a Supreme Court Justice would retire when the current President was of the same party as the President who nominated you. That was the case even when your judicial philosophy might have "drifted" from where it once was.