The trouble with transhumanism is that it is speculation regarding biological and technological evolution. There may be modest advances in technology and biomedical engineering in the near future, but the prophesied or hoped-for far-reaching developments are unlikely to benefit current promulgators and enthusiasts. Evolution is too slow a process for that. Nevertheless, transhumanity (transcended humanity) is probably inevitable if we don't become extinct first.
"What is great in man is that he is a bridge and not a goal." -- Friedrich Nietzsche