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I did actually try to search for topics on multiple cores vs MySQL, but I wasnt able to find anything of much use. Elsewhere (on Hacker News for example), I have indeed come across statements that PG scales better on multiple cores, which are usually offset by claims that MySQL is better.
However, what I did find (http://www.pgcon.org/2008/schedule/events/72.en.html) was titled "Problems with PostgreSQL on Multi-core Systems with Multi-Terabyte Data" (interestingly, published by the Postgresql Performance Team @ Sun)
Ergo, my question still stands - maybe my google-fu was bad... why is why I am asking for help.