I can imagine what a burden it must be to optimise pages for both google and yahoo.
Here in Belgium almost nobody uses yahoo. I can count the visitors I got from yahoo up till today on two hands 
update: I looked at my statistics and Yahoo and MSN TOGETHER account for 1,37% of my search engine referrals.
It seems extremely low, but I think ppl from other european countries will get about the same percentage.
Elgoog, what about you?