I think people understand that their calculator can do arithmetic much faster than they can. No?
This could simply be an indication that the brain's architecture is not well-optimized for arithmetic. It doesn't necessarily imply that calculators are faster.
The computer I had in 1999 had occasional difficulties in carrying out real-time emulation of a gaming console released in 1990. That doesn't mean the console had better hardware.
I wrote a new Singularity FAQ for the Singularity Institute's website. Here it is. I'm sure it will evolve over time. Many thanks to those who helped me revise early drafts, especially Carl and Anna!