Hi, My company is developing GIS related technology. As a result we are looking into employing a map server for the display of water infrastructure networks. I've start investigating tilestache as an optional solution for our performance issues relating to the layers display.
I cannot comment on the memory consumption.
I'm guessing that if you deploy tilestache as a wsgi using something like gunicorn you can define multiple workers which would result in multiple cores being used (never tried this myself). There could be issues with file locking though if tilestache tries
to write the same tile from seperate workers (metatiles)... It appears that the seed command doesn't support multiple threads / processes.
If you are still in the investigation phase I would have a look at MapProxy and MapServer MapCache which are great open source solutions as well.