A few months back I was considering Starting a danish language user-edited newspaper, so I was interested to hear what made OhMyNews a success. Key points that aren't obvious just from blogging:

• The editing staff is paid and professional and holds itself to the standards of mainstream media. Facts are checked, stories are pulled (30%) when they don't check out
  
• Even though the site is amateur-based, there's a built in tipping system, allowing readers to reward good copy financially
  
• (so OhMyNews is actually a market for newscopy)
  
• The other upside for writers is the exposure - but as the example of Flix proves, you really, really don't want to reward your users without also applying strict quality control
  
• While personal media is great, there's rewards in scarcity: It matters to writers to get on OhMyNews because it's hard