The figures for this vary so much. I have seen everything from 140 million to 350 million.
In an English paper I saw a very low figure, 140mil I think. I got suspicous and checked it. The figure corresponded with Wikipedias entry for the population of Russia... But according to that definition, Iti-Ogo, Zaya and many others on this forum are not even included.... Sloppy and poorly informed journalism!
On the other hand, last year the Swedish ministry of education wanted more kids to choose Russian as foreign language in secondary school. So the "Guide to selecting foreign languages in secondary school" cited the very unrealistic-sounding figure of 300 million... That figure must include everyone who lives in any ex-USSR country. This broschure also claimed that "Russian is widely spoken in the other Slavic-speaking countries such as Poland (...etc)". I don't know how true this is really but I've met a few Bulgarians and Serbs who definitely could speak fluent Russian.
What's your opnion on this?