Personally, I think the main difference is about the focus the media place on certain events.
If it hadn't been for all the media jumping on the story, nobody would have even cared that some egocentric sect leader wants to burn qurans. Maybe just a handful of people would have even attended the event. It was the media that claimed it was a big thing and might lead to conflicts, thereby making it a self-fulfilling prophecy.
On YouTube on the other hand there are a number of videos about burning palestinian flags or qurans etc. Nobody cares, because the media don't massively report about it.
Or take the Muhammed-caricartures: When they were first posted in the xenophopic danish newspaper Jyllands Posten, nobody really cared. Just a few days later, the caricartures were also printed in an egyptian newspaper - again nobody cared. The whole story got big when the media massively started to jump on the story and became a catalyst.
And big news stories are always when something really unusual, unexpected happens. If a celebrity well known to be gay has sex with a man, nobody will care. If however a well known republican who usually claims homosexuality is evil is discovered having sex with a man - now that's a story. If Taliban kill and cut off body parts from civilians - that's sad, but not very interesting because they are labeled as the bad guys and you'd somehow expect them to do that. But if US soldiers do that, that's a completely different story.
