Depressed Metabolism here notes the existence of a double standard when it comes to the science and practice of cryonics - actually one you'll find exists for all serious endeavors in life extension, such as SENS research: "One of the most predictable features of public debates about cryonics is that those arguing in favor of cryonics are held to more rigorous standards than those seeking conventional medical treatment. Advocates of cryonics do not just have to prove that cryonics will work, they are also supposed to solve problems like overpopulation and the presumed boredom arising from expended lifespans. To some, people who make cryonics arrangements have an inflated perception of their own importance and should just forgo such selfish attempts to extend their lives. The default position seems to be that people should not exist and that life needs justification. Could you imagine such antinatalist rhetoric being employed when a person seeks conventional medical treatment to extend their life? We can't, and such responses are quite indicative of the fact that people are not interested in serious evaluation of the cryonics argument."

Link: http://www.depressedmetabolism.com/2011/07/29/the-double-standard-about-cryonics/