But actually, it won't be coming to the U.S. officially at all. Like all Sharp GX-series phones, it's exclusive to Vodafone (Europe).
But usually, they release a non-branded version for sale through other channels that don't compete with Vodafone, or someone finds a way to unlock a batch of them and sell them online anyway. Either way, I expect some online importers will have this for sale sooner or later.
Since it only has GSM 1900 for the U.S., you'd pretty much have to use it with T-Mobile.