iTunes question -- multiple users

IdRatherBeSkiing

Sherbet is NOT and NEVER WILL BE ice cream.
Oct 11, 2008
27,328
13,887
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Toronto, ON
Since my wife got her new iPhone5, my son has been given her old iPhone3GS. Right now it is still configured with my wife's iTunes account although we have logged her out to prevent new charges.

We are going to wipe the phone and create a new iTunes account for my son. He has a computer but the internet is not great. I was wondering about just signing myself out of iTunes and creating a new account from my PC.

My questions are as follows.

1. Will iTunes use the same music library or does it have a separate copy for each iTunes user?
2. Will it get confused between the 2 computers and 2 phones?
3. Will the iCloud PC add on get confused?