That's exacly opposite. That nut job Chavez is sitting on georgeously clean crude. The dirtier stuff from Venezuela is still comparable to the better crude from Iran (Which is why we don't import Iranian crude.
http://www.google.com/search?num=100&hl=en&lr=&rls=GGLG%2CGGLG%3A2006-09%2CGGLG%3Aen&q=venezuelan+crude++sour
I get conflicting information about Venezuelan crude