Having said that, if you want to 'sell' cryonics as part of brainwashing package, or a religion, I'd be the first to say that it can probably done. It has been my observation that you can get people to do almost anything if you rob them of their will, and subvert their reason. For myself, I don't think that's a good idea.
The concern that lesswrong might be a cult has been dealt with extensively already.
Like it or not, lesswrong is likely one of the greatest allies cryonics has right now -- and I would say this is not so much because of all the new recruits and fresh blood, but because of the training in rationality that it provides and ultimately injects into the cryonics community (among the other communities it intersects with). Because of this emphasis, lesswrong is actually pretty good insurance against cryonics becoming a cult.
I just read over my post, and I didn't say (or imply) anything about lesswrong being a cult. I know almost nothing about lesswrong, beyond reading interesting posts here, from time to time, usually as a result of google searches. My proximate reason for posting here was that Gwern suggested I do so, and also pointed me specifically to this discussion. So I guess my question would be, "Why would anyone think that I would think lesswrong was a cult?"
My remarks about "selling cryonics as part of a cult" are long-standing ones, and go back...
From Mike Darwn's Chronopause, an essay titled "Would You Like Another Plate of This?", discussing people's attitudes to life:
Conclusion, graphs, and references in article. As usual, I recommend reading Chronopause.com as Darwin has many good articles; to quickly link a few: