"They do seem to like to plan major atacks on significants dates 911 for instance."
Curious - Why do you think they arranged their plans to fit OUR calendar rather then the Islamic calendar ?
Answer - Significant to the enemy which is us. Another example would of been the Islamic Algerian national Ahmed Ressam, arrested at the U.S./Canadian border in December 1999 and charged with plotting to bomb Los Angeles International Airport on the eve of the millennium. I turn your question back to you, what does New Years mean to someone following the Islamic Calendar?
"I turn your question back to you, what does New Years mean to someone following the Islamic Calendar?"
It means a lot of people and a lot of publicity - maximum impact - worldwide networks are in place to instantaneously transmit the info to billions of people worldwide. For example, the Winter Olympics in Munich. The actual numerical date didn't matter.