Burn a Koran Day will go ahead.
OK, so I don't agree with fundamentalist Christians on a lot. Here's a list of exceptions to that rule.
1) They have every right to burn the Koran without fear of physical reprisal, either from their government or from other citizens.
2) They should have that right (and I'd feel the same if they were burning a book I valued).
3) People really are more afraid of upsetting Muslims than Christians.
4) Although I'm not terribly impressed by the individuals involved here, the real assholes of the piece are the folks in predominantly Islamic countries who whip up a riot at the drop of the hat.
Regarding point #4, can Gen. Petraeus & co please note: these people cannot be placated. They cannot be bought off by our silence on religious matters. And this is because they're not really doing it for religious reasons; they're doing it because it enhances their personal power in their local community.
As long as there are people who have a personal incentive to riot, riots will continue to happen. (If no excuse comes along, they'll make stuff up.) It's simple socioeconomics.
It's like trying to talk rationally with a belligerent drunk bloke who's accusing you of spilling his drink in a pub. It doesn't matter whether you really spilled his drink. He's not there to talk rationally, he's there to thump someone. All you can do is ignore, evade, or punch back.