Just fyi, here are a couple of articles about the trend you described on the weakening power of international oil companies:

Sacha Kumaria: A growing number of industry voices suggest that the era of the vertically integrated supermajor may be over, and that IOCs have been unable to adapt to the new global business environment…
http://online.wsj.com/article/SB118842251171812645.html?mod=googlenews_wsj

What is new is the increasing difficulty IOCs have in finding countries in which to replace their reserves that do not have government monopoly over exploration and production. Accordingly, the economic and geopolitical value of the control that NOCs exert on their reserves is increasing…
http://www.ft.com/cms/s/f8f91202-46d9-11dc-a3be-0000779fd2ac.html