Yeah well, maybe you haven't noticed but English is an international language that is more or less known everywhere, whereas Russian isn't. Also it should be pointed out that Russian uses different alphabet, what makes it even more "exotic". The fact that you don't like English is meaningless, as it is an international language, used by organizations to contact. So learning language, with its very different alphabet, sufficiently to understand what the campaign heroes will say is rather impossible, one would need few months, even years to do it. The international community is here neglected, even by officials, which is quite bad and demoralizing. Not to mention the Akella's bad organization, it aspires to be a worldwide known publisher but at the same time makes such horrible mistakes as not providing a publisher for one of its most known games.

I wonder if Diablo 3 or Starcraft 2 (or any other game you would die to get) would be only in Japanese you would also say: Learn it or wait, without any complains, just taking it for granted.

And seriously speaking, I suppose that everything will be normal with English version of the Game. You should just wait for a season.

About voices. I really doubt that there are many.
Dunno about campaign dialogues, but smth tells me they are not voiced.
Well, maybe there are some leader acknowledgments, but it's no big deal if they will not be translated. It'd even be a feature, like LotD speaking in latin, which few people know.
Videos may be a problem. Mission loading screens may be a problem. Campaign texts, if they are closed in resources, may be the biggest problem.

update
Campaign texts are not a problem.

update
Qumi, some good new for the english-speaking part of the comunity.
source
Q: When will the europian/american realise be and who will publish the game in these regions?
A: This is closed information at the moment. Negotiations with international publisher are at signing final stage.