Common interests are what characterize a corporation or union and most political party structures (ideology does not motivate most ruling parties much). Very often there is tension between these interests, and the economic choices they imply making in common, and the common values that people might rather pursue when there is no economic groupthink pushing them a certain way.
Types of countries tend to be defined more by common interests than by say adherence to international law.
Getting people to declare common interests is quite difficult. The whole financial capital system makes it easy to hide who has what interests in common with who, and this has only gotten harder to track with globalization.
Essential projects tend to be those that have common interests and common values with Consumerium - other than that, there may be nothing more we can say. The Consumerium Governance Organization will have to make day to day decisions about where to trust in other projects' or groups' common interests.