As the eighth most popular spoken language in the world, it makes sense that Russian would join English, Spanish, French, German, Mandarin, Italian, Portuguese and Arabic. If you're only texting via Skype chat, rather than video calling, Skype also supports text-to-text translations in over 50 different languages.
With so many Russian dialects, Skype Translator is bound to be a little clunky with the language at first, but the company claims its built-in machine learning layer will continue to improve the translations as more and more people use it. While the feature will technically translate between any of two of the supported languages, it works best between English and a second language -- but it will also get smarter about that as it gets more use over time.
For now, Skype Translator only works for the Windows Desktop version of Skype.
Update: This post has been updated to note that Skype Translator can handle voice-to-voice translations, in addition to voice-to-text.