The valedictorian of my high school was the only student to leave the state.
I guess having the highest GPA gave them more opportunities in other states.
Yes, they went on to become very successful from what I could tell. 
It's interesting that that title is not used frequently in places like Austrailia and New Zealand.
I did not know that. Is there a ranking system in schools over there though?
It seems that the highest-ranking student in those areas is called a "dux" meaning leader and may or may not give a speech.
Is giving a speech up to them or the school? Our valedictorians here can be sensored, and their speeches are carefully scrutinized.
I think in the US at least, the valedictorian always gives a closing or farewell statement at graduation.
Yes it is, some people may cry or laugh but in my case it was very boring.
Some places award it to a student based on their contribution.  Maybe those speeches are more fun.