If I currently have a Blackberry on a family plan that has unlimited data. WilI i retain the unlimited data plan if I upgrade to the iphone 4s? Will the iphone 4s be global ready/capable? If I am eligible for an upgrade now but my contract is not up until December, can I upgrade to the iphone 4s? I have been reading that the Verizon network is much slower than AT&T when using data for apps. is this true?