I'd kick Kirk Douglas off the list just for brutally raping Natalie Wood and putting her in the hospital for a week, doing permanent serious physical damage (or so says Robert Downey Jr. - and as this week's Natalie Wood news has unfolded, it seems there's a tape of a statement that Robert Wagner threw her overboard in rage and said something like "f**k, let the bitch drown.")
I'm unaware that Robert Downey Jr. has been substantiated as being one of the people circulating the rumor about Kirk Douglas raping Natalie Wood. That Robert Downey Jr. himself is involved in circulating the rumor is itself, as far as I know, just a rumor.
No, I'm pretty sure he outed his online identity to confirm the veracity of the rumor, saying it came straight from an actress he starred with in a certain movie, which turned out to be Natalie Wood's daughter. I was following that particular thread and got Natalie Wood's daughter's home phone number before he reconsidered and edited his comment.
He figured he was done for a long while to deal with the career fallout from posting the very brutal details of what Kirk Douglas had done, but it didn't seem to have many public ramifications. He still comments in between movies, and he left a really nice 9/11 tribute last week. His wife also comments there sometimes. I think he's one of the best and funniest writers on the web, even as a semi-anonymous commenter that everybody knows is RDJ. He writes from the heart like few can.