User generated content meets mainstream media

Firstly - when does 'user generated' become 'user rewarded?' I'm still curious to know whether the blogging and amateur video phenomenon that has swept so many parts of the online world will eventually deliver a wave of content-fatigue, as on-paid contributors grow tired of their efforts and move along to other activities. We've already seen how fickle audiences can be in terms of leaping from one new hot thing to another. And how long will consumers be happy to see third-parties raking in revenue based on their efforts?

The second is how user generated content changes the game-plan for traditional media content creators (including, I suppose, myself). There are some interesting factors coming in to play at the moment as advertising revenue continues to migrate from offline media on to the web. I've been hearing that the advertising yield of a web page is roughly 10 percent of that of a magazine page, meaning that publishers need to raise 10 times the revenue - or publish and sell 10 times the number of pages (not of course factoring the revenue from the cover price of a magazine nor the cost of its production). We're seeing publishers increasingly pushing citizen journalism media (check out the Chicago Tribune's Triblocal site)... will this be enough to make up for the shortfall in revenue, or will content creation in future be a very low-margin game?