I'd make a distinction between the "Transhumanist movement" and a larger group of people - many of whom probably read io9 (and Boing Boing, Slashdot, Wired, and on and on). There are lots of people out there who are fully cognizant of transhumanist views, and who are interested in - and possibly supportive of, or ambiguously curious about - say, cyborg body enhancements, or memory enhancement, or ending aging. And in fact, my friend Ramez Naam argues that anybody who wears glasses or takes birth control pills is a transhumanist and so he refuses the label as sort of banal.
If you look around at the serious efforts to make progress in longevity science or other means of postponing permanent death, you'll find members of the transhumanist community involved and amongst the most vocal supporters: the Methuselah Foundation; Alcor and the Cryonics Institute; the Immortality Institute. Similarly in the fields of strong artificial intelligence and advanced nanotechnology - organizations like the Singularity Institute, the Future of Humanity Institute and the Center for Responsible Nanotechnology are outgrowths of the transhumanist community of the 80s and 90s. Collectively these organizations and others have raised tens of millions of dollars over the years.
The transhumanist community that was - once upon a time - clearly defined at the edges, and largely in the business of talking rather than doing, actually attained its immediate goals. This is to say its members and the general progress of technology brought the transhumanist view to a much broader audience. Ideas once strange and unthinkable became accepted as plausible extrapolations of present trends; which was always the case, but some people can see farther ahead than others. During this process, the transhumanist community became diffuse at the edges and no longer ahead of its time; most of the core ideas and goals spread into the mainstream, changing along the way. That's the best end possible for any subculture, a victory in the sense that all of these ideals - bioengineering, the defeat of aging, enormously lengthened healthy life spans, artificial beings, molecular manufacturing, and much more - will come to pass. Too many people are thinking about these goals now for any but the impossible to vanish from the horizon.
It's just a question of when it all comes to pass - which is a very big question when it comes to the development of medical technologies that can rescue us from aging to death. Soon enough, or too late? What are you doing to help things along?