In the comments to my previous post I read what one of our readers (Tampa Pirate) will come to Moscow as independent traveler soon. And I have a good news to him.
New Hop-On Hop-Off double deckers by City Sightseeing came to Moscow last week.
I don't know anything about quality of service yet but now it's only one route with commentary on Russian, English and German languages. 24 hours adult ticket cost 600 roubles.
Full service with three routes plan to start only next summer.