Samsung Galaxy S III (Verizon)

I have been trying to get an answer to this but haven't seen any info online. I know Verizon is promising to update the SGS3 to have global capabilities in the future. I will be spending significant time in Europe where 4G is a ways off, and want to be able to use HSPA+ while I'm there. My understanding is that Verizon's version, once updated, will allow for global roaming but using GSM.

My question is this: will the chipset have HSPA+ available that a firmware update (hack) could unlock? I know T-Mobile's version has HSPA+ but no LTE and of course no CDMA. I will still spend significant time in the US and don't want to give up my Verizon unlimited data and want to have 4G while in the US; otherwise I would buy the international version.

Does anyone know if the chipset in Verizon's version of the SGS3 will be potentially unlockable to allow for HSPA+?

Thanks in advance.