My first Google hit for "transhumanism" is Humanity+...

You're right. I guess I'm using the same metric as JoshuaZ (who's the best marginal use of my dollars?) and I'm fairly convinced that's existential risk, so I was discounting several non x-risk focused transhumanist charities, perhaps unfairly.

And apologies for implying you were solely a "loud contrarian". I didn't mean to imply that was your primary purpose for posting on LessWrong, just that I'd noticed many comments by you recently along those lines, and I was having difficulty interpreting your skepticism.