Their position is almost similar to the social democracies. Many Nordic countries were under the threat of revolution during the time of the USSR, so the ruling class(es) set up concessions to appease and prevent a full-out revolution by the working classes.
Cuba and Vietnam are still being run by people's parties, but they are appeasing the national bourgeoisie and international bourgeoisie for economic development in productive forces, consumer goods, not being harassed by neoliberalism as much, etc. I am under the impression that most of the "capitalism" allowed is petit bourgeois style -- there is capital owned and worked by the same people. The important thing, however, is that the government is actually democratic centralist or whatever...