http://en.wikipedia.org/wiki/Millennium_Development_Goals#Pr...
The problem, to me, is more of a logistics problem, because once you get more than ~100 people in an organization, you start losing the immediate connection with them, which means you care less about their well being, because you don't know them. The issue is managing people, and meaningfully punishing ne'er-do-wells.
Leninism worked, we know for a fact that it worked, at least until Stalin took over and made it something worse that ultimately didn't work.
I don't think that [nor am I inclined to think did Marx]. I think capitalism exacerbates it drastically to a markedly negative effect (though not so negative as say malevolent dictatorship). Moreover I don't perceive inequality as detrimental, it's a truism that none are equal after all.
However I do certainly have communist beliefs about the best forms for society to adopt.