Theoretical situation.. first hand of the WSOP main event

I apologize if such a thread has been created before, but here we go...

Imagine you are a pro, say someone as good as Phil Ivey. It is the first hand of the WSOP main event. You are in the BB. Everyone folds to the SB, who moves all in.

You look down and find AA. Regardless of what you believe the SB to have... is this an instant call?

Some people seem to argue that someone as good as Phil Ivey doesn't need to take such a quick risk, even tho he is a very likely favourite to any of the SB's range of hands. Some would argue that he could "out play" many other plays without having to risk all of his chips.

Then again, winning this pot would put Phil in a great position to be very aggressive, and dominate the table, and perhaps the rest of the tournament.

Some argue, if you're not willing to put everything in with AA in this situation, maybe you don't have what it takes to win the tournament, since you obviously need some luck to get there anyways. What better than to move your money in with the best hand possible preflop?

Thoughts?