Social Media and Shaving Occam

Here is a good rant about social media and the way Spinn is going the way of Digg, which went the way of StumbleUpon, which went the way of Technorati. Why is it that as soon as something new in social media is released, the rush is on to ruin it?

Shaving Occam: Tony Wright's Blog: Social Media's Dirty Little Secret
The dirt secret of social media is the fact that there are hundreds, if not thousands of individuals successfully gaming these systems. . . . Don't cheat. Don't lie. Don't use 1,423 profiles on 200 IP classes with e-mails all over the place to get there.
I have used Digg, StumbleUpon and Technorati, but lost interest before Spinn and all the other social media ranking sites were released.

Which social media sites do you use? Do you believe that people are gaming the system? How could the system be changed so this could not happen? What success have you had with social media sites? Share your experiences without spamming the comments. The most useful comment will win 1000 Entrecard credits.