In a recent piece for Vanity Fair, Christopher Hitchens makes the following comment:

somebody has written to me from a famous university to suggest that I have myself cryonically or cryogenically frozen against the day when the magic bullet, or whatever it is, has been devised. (When I failed to reply to this, I got a second missive, suggesting that I freeze at least my brain so that its cortex could be appreciated by posterity. Well, I mean to say, gosh, thanks awfully.)

The context (in which this is listed among various pieces of pseudoscientific treatment advice he has received) makes it clear that he is dismissive of the idea.

Which is a shame, needless to say.