This topic will turn rather quickly to something like "Should skin colour affect the way people are allowed to live?", so I'll try to slow it down.
Obama does represent a change for America.
Whether or not he should be president is entirely based on opinion.
There is no way that there can be any solid facts brought to case.
Sure, you can go by whether or not he is doing a good job (also opinion based), but there is almost certainly a person who could do it better in one way or another.
So yeah, I don't see much to discuss. Still, try to think of something interesting and debatable about this, and I'll do my best to discuss it.