The Supreme Court today issued a 5-4 opinion with O'Connor in the majority (the first this Term, I think). The opinion holds that state sovereign immunity does not prevent a bankruptcy trustee's suit against a state agency. This may sound dry (and it is), but state sovereign immunity has been a hugely contentious issue in the Court in recent years, with virtually every case decided 5-4 -- usually with O'Connor joining Rehnquist, Scalia, Kennedy, and Thomas. This time she joined Stevens, Souter, Ginsburg, and Breyer, and the other four (including Roberts) were in dissent. So there's a nontrivial chance that, had the opinion been held up just another week or so, the case would have come out 5-4 the other way.
I highlight this because some might have been inclined to assume that justices on the losing side of a 5-4 with O'Connor in the majority would strategically delay the completion of their dissent so that they could, with any luck, get a different result with Alito. After all, that's what we would expect legislators to do.
I suppose that cynics will suggest that the dissenters allowed this case to be released precisely to create this favorable impression among the citizenry/cognoscenti, but that seems farfetched. Less improbable is the possibility that their intended audience was their colleagues -- e.g., that they allowed this case to be released because they wanted to hold up another case and used the release of this case to show their colleagues on the Court that they were not acting entirely in bad faith. But I think the odds of that explanation being true are pretty slim. Very likely the real explanation is that they acted honorably, sticking to their normal schedule.
The case is Central Virginia Community College v. Katz.