On the whole, it looks good to me. The approach seems a bit more directly proselytizing than most recent Singularity writing, particularly the specific mention of SIAI in the last paragraph, but I'm not sure whether that's a good or a bad thing.

Some nitpicks:

Would donors and activists support the causes they currently do, if they had full information, better minds, and deep reflection to guide their judgment? Thomas Pogge is one thinker who believes that we wouldn’t

"that they wouldn't"?

attending to the possibility of a negative the Singularity

remove "the"

Muelhauser

"Muehlhauser"

ETA: also, you might want to replace "better minds" in the first sentence with something more specific, like "sharper minds".