A pathetically brief search shows no threads about this, so I'll go.
Iran are claiming that if you cut out and rearrange the numbers in the 2012 Olympic logo, for reasons best known to Iran, then you can spell out ZION, which is to do with Israel, which is insulting to them, so they won't be turning up. The berks.
Amusing developments today: David Cameron said 'If the Iranians don't want to come, don't come, we won't miss you.' Now THAT's diplomacy.