an interesting piece of research by silicon alley insider shows the average ad revenues per user for a number of different media sites.
its interesting to see how quickly facebook has climbed and that Yahoo! is still monetizing so effectively per user.
They compare this to the projected twitter revenues, which dont look that big at the moment (compared to the others in this market). however, innovation and new ideas are sure to prevail as new models are created.
but back to the revenue projections. when compared to historic revenue analysis, we can see that Yahoo has been slipping and facebook growing quiet steadily and that compared to search giants google, the ad revenues taken in are small.
more analysis of revenues:
web revenue mechanics to make $10M