I've posted a small comparison of using the default font size of 770 and using 11 px version by modifying gtkrc file. I recommend everyone to have a look at how user experience differs between them.

http://konttoristhoughts.blogspot.com/

I have permanently switched to using 11 px fonts and I'm not coming back. Every single app is much better off with smaller font than it was with the humongous default font.