If a revoltion still occured, who knows what would have had to Alaska there, as it wouldn't have been very populated and may have been invaded by Western powers, seeing as it borders one. So it may have been taken over then, or if the Alaskans didn't want a part of it, even declared independence.
I don't know if Imperial Russia could have lasted though, that size of a country and not exactly being very advanced, how would it have made it through the 20th century, let alone fared in WWII?
If the Soviets retained it, I wonder how its riches may have impacted it. Plus, the sphere of influence would then include Canada. Heh.. And the proximity would have been soooo much closer, in a meaningful way, to the US. I don't know if it would have changed much, but who knows. Who needs Cuba if you can get nukes on the southern strip of Alaska. Or, combining that with Cuba, and you got a missile crisis and a half for the US. Who knows, maybe things would have been very different.
Any Ruskies angry about their loss of a potentially vital, giant piece of, albeit useless, land? That said, the Russians seem to have a way of colonizing what we may consider uninhabitable, so maybe Alaska would be bustling... or just a threat even worse then being sent to Siberia.
Another q, how did Alaskans feel about being across a narrow strait from the Soviet Union during the Cold War?