Well, maybe not a tell "all," but it sounds like he's planning to say a lot. Via Barton Gellman, on Dick Cheney's forthcoming book about the Bush Administration:

Robert Barnett, who negotiated Cheney's book contract, passed word to potential publishers that the memoir would be packed with news, and Cheney himself has said, without explanation, that "the statute of limitations has expired" on many of his secrets. "When the president made decisions that I didn't agree with, I still supported him and didn't go out and undercut him," Cheney said, according to Stephen Hayes, his authorized biographer. "Now we're talking about after we've left office. I have strong feelings about what happened. . . . And I don't have any reason not to forthrightly express those views."

Of course, if history is any guide, this might just be disinformation spread by Cheney's agents-- in this case to secure a favorable book contract. We'll see.