I realized something about DU today. [View all]
The mainstream media in the US today has been consolidated into ever fewer hands, and as a result, those who are higher in the hierarchy of these organizations make stratospheric salaries while those at the bottom just are work-a-day types like anyone else. This fact helps explain why mainstream media personalities and their programs (like This Week) are right-leaning and GOP-friendly - media jobs attract those individuals who want to make big money, and in return, they scratch the political backs of those who favor their taskmasters' interests and their own interests - the GOP.
DU, on the other hand, may not have international news bureaus or other types of news departments, but it does have hundreds and thousands of political news junkies who come here from all over the world to share and discuss information relating to issues of interest to liberals and progressives - i.e., hunger, homelessness, outsourcing, unemployment, crony capitalism, political corruption, etc.
In that respect, where there is a real lack of liberal media personalities in the US today who are willing or able to do real muckraking journalism, DU (and other social media sites like Kos) help serve as a kind of modern popular press, serving as a check on the status quo's prevailing powers.
Yes, in the big picture, DU is not even a ripple on the surface, but I am grateful for it - I get nearly all my news here. 
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