Russian language is present in Ukraine in everyday life. Kiev remains a largely Russian-speaking city, and of course the south and east of Ukraine will probably remain Russian-speaking. But the Ukrainian language will become more and more relevant throughout the country, and eventually Ukraine will probably end up being a properly bilingual and partly trilingual country
There are waves during which the status of Russian language is discussed in Ukraine, and it's basically always the same sort of argument around whether Ukraine should have one or two official languages. This discussion is going to continue, because the country is divided into a Ukrainian-speaking part and a Russian-speaking part. Recently, there has been no particular increase in the salience of the issue in Ukraine. These discussions were also taking place here five or ten years ago.
Recently, Mr. Yanukovych declared that in the near future, the Rada will pass a law about the two official languages. But he has declared that before, and Leonid Kuchma had declared to do so in the 1990s. I'm not sure whether this will ever happen, because there has been a lot of such talk, and it has never resulted in any real attempts to change. The problem is also that this would require a change in the Constitution and for a constitutional amendment there would have to be a two-thirds majority in the Verkhovna Rada, the parliament. That is, even for Yanukovych, not so easy to collect for such a constitutional change.
There is electoral campaigning going on now, in October there are going to be parliamentary elections. And this question is raised, obviously, for that reason. The question usually comes up before elections, and the pro-Russian candidates - in this case Yanukovych (like Kuchma before him) - offer the introduction of a second state language. But Ukraine, for more than 15 years, has officially had only one state language, and it will probably stay that way.
Some political scientists believe that this declaration also has to do with some kind of pressure on Russia. But I'm not sure that one can link gas prices to the introduction of Russian as a second state language. These are two very different issues and it is difficult to believe that there will be a connection between the two in the future.
As paradoxical as it may sound, the best thing that Russia can do to promote Russian language in Ukraine would be to promote Ukrainian language in Russia. Why are people here reluctant to accept a promotion of Russian language and culture in Ukraine? One reason is because they don't see an equivalent on the Russian side. There are Russian TV stations that one can watch in Ukraine, there are chairs for Russian literature at Ukrainian universities, and there is lots of Russian literature and mass media present in everyday Ukrainian life. But nothing even remotely equivalent is present, on the Russian side. There are only two relatively significant Ukrainian studies centers in Moscow and St. Petersburg. Russians cannot watch Ukrainian television in Russia (although much of it is in Russian language), and ethnic Ukrainian culture is largely absent in Russian cultural life. If that would change, then the attitude in Ukraine toward Russian culture and language would also change for the better.
To summarize, Russian language will remain present. It is present in Ukraine in everyday life. Kiev remains a largely Russian-speaking city, and of course the south and east of Ukraine will probably remain Russian-speaking. But the Ukrainian language will become more and more relevant throughout the country, and eventually Ukraine will probably end up being a properly bilingual and partly trilingual country (English gaining more and more importance). It is already to a great extent bilingual now - many Ukrainians speak both languages - but this feature, bilingualism, will become even more prevalent, with the south and east becoming gradually ukrainianized.