I'm not sure what Google's figures are for Russia in 2008 but they sure are going after that market with a vengeance. See this article posted today:
The internet market in Russia is expanding at a massive rate and IMO Yandex is not well placed to take on the gathering forces that are beginning to attack it. My limited dealings with them indicate they believe they are impregnable and are acting in a manner that reminds me of Yahoo when they were top of the pile. Arrogance personified.
One example of this is that Yandex will only deal with you if you have a Russian bank account. Impossible for Brits like me. I know that there are government restrictions in Russia that maybe I don't understand but other companies in Russia deal in $ and £ bank acounts. Yandex have not accepted that Russia is not an island and that they need to look outwards not inwards.
Google and the other sites you mention are going to win the day. I especially believe this of Google. The Russian markets (like the Chinese) are in a different economic cycle compared to the West and if Google can conquer these markets they will spread their risk of economic downturns.
From the few Russians I speak to, I get the impression that they believe that the construct of the Russian language, and the alphabet, is defence enough against the Western internet invaders. Possibly Yandex think so as well, if so they are wrong. Russian is a whole pile easier compared to Chinese.
Just realised I'm ranting, so I'll stop here!