Factory unlocked phones-iTunes store iPhone 4

I am in manila for the next year and contemplating trading in this piece of garbage Blackberry for a factory unlocked iphone4. Supposedly I can use it on any carrier, but I dont understand the details, its hard to get consistent information here.
Can anyone tell me whether these factory unlocked iphone4s can access the itunes store? I had an Iphone3G(ATT) before this and many apps that I already paid for, etc, which I would want to migrate over to this phone as well.
I dont really want to have to jail break. Just want to continue using one of the prepaid phone plans here that includes unlimited data and use the phone, including with itunes to get my apps, etc.
Possible?
Mac OS X (10.5.4)