The arrogance caused (typically in females) by having more than 1000 friends. People with Facebook Arrogance typically treat all people whos friend requests THEY accepted as 'creepers' for liking/commenting on their statuses EVER.
Girl 1 adds Guy 1
Guy 1 messages Girl 1 "Hey"
Girl 1 posts a status about him being a creeper and blocks him because she has facebook arrogance.