The Washington Post has the scoop, including what may be the key sentence: "She has written a memoir, which she is now shopping to publishers."
UPDATE: McEwan in a interview reveals that she had an intimate relationship with Thomas. She says he liked pornography, especially depictions of large breasts. What is the point of revealing something so incredibly banal? Does it corroborate Anita Hill's testimony in any significant way? The issue, in the confirmation hearing, was whether Thomas engaged in sexual harassment in the workplace. McEwan is talking about his private life. First, that's really creepy. Imagine if a man revealed private, sexual things about a woman. McEwan even admits that she's speaking now because she is politically opposed to Clarence Thomas. She doesn't like the way he's deciding the cases.
Since McEwan never says that Thomas talked about pornography in the office, the supposed corroboration is virtually nil. It's true that if we know a man is interested in pornography, it makes it more likely that he talked about that interest somewhere, more likely than if we didn't know whether the man liked pornography. But huge numbers of men are interested in pornography, and only a small subset of them who pester women by talking about it graphically in the office environment. So it just doesn't matter enough to bring it up.
McEwan also talks about the way Thomas thought about women, but it comes across as sheer speculation. She somehow knows he thought about whether women he met in the office would make good sexual partners. Again, this is perfectly banal. It says little about how he might attempt to initiate a relationship with a coworker. Doesn't nearly every single adult look around at other people and think about whether they are attractive and might make a good sexual partner?
This is just sad and embarrassing.