commodity production, anarchy of production, ownership of the means of production in private (Collective) hands, etc. Basicly a new form of capitalism. You can read about it on MIA under Tony Cliff.
Well there are other things that differentiate capitalism from feudalism, mostly private ownership, markets, a "flow of money." However the USSR had none of these, so I'm confused as to why it was "state capitalist," any more than a feudal country could be considered so.
quite a few things, a key is large scale commodity production, the ruling class, etc, why do you ask?
What makes capitalism different from feudalism?