I know I run the risk of being modded down, but the choices you have just detailed are the exact reason why Linux will never fill any significant void. While I like to play around with Linux and make informed decisions about which option to use. I would imagine 90% of users would rather have a machine that just worked.

It could equally mean that google has better query expansion mechanisms. If google manages to return more documents containing synonymous terms then its relevant set would be bigger.

DaClink