I have massive respect to Yoast and he definitely nailed the SEO plugin, however I prefer AIO over Yoast.

10M downloads definitely speaks for itself and that is going to be very hard to beat, as you mentioned Jeffro, Akismet didn't even reach that and it's also default plugin on top of that.

Only one can talk the talk and walk the walk 10,010,519 times ;)

Cheers,
Emil