In a way they will be sharing 4G depending on how you look at it... basically Sprint is offering Metro some of their 4G LTE service due and Sprint sees it as another way to make money so are charging Metro for it and that is why Metro is raising their prices. Now, the obstacle that we have come across is that we are wondering if Metro is grandfathering us in because...
1. It is good customer service and they dont want to lose existing customers
OR
2. Because the change if/when it takes effect may not effect EVERYONE on a 4G plan in the nation thus them not wanting to charge the people who it wont be affecting more for nothing to change speed wise but charge more for it.
The reason why #2 is a possibility is because of the fact that we are being grandfathered in with our current plans. Now if we were ALL forced to move to the newer plans then I would have to say that if this WERE confirmed to be true sometime in the very near future then it WOULD affect everyone and EVERYONE would see a speed increase but like I said, we may be getting grandfathered in due to this possibility.
Also, yes this IS a possibility because Sprint HAS in fact started moving to LTE and is in fact at the least ALMOST ready for it to take stage. Galaxy Nexus is beast... I would guarantee that this move by Sprint to LTE is because they wanted the Galaxy Nexus and didn't want to pay higher prices for a WiMax version for only them AND because the new iPhone will PROBABLY support it so they STILL wont have to get it made customly for their network because Verizon will be getting an LTE version also(Besides Frequency Bands Changes/Differences).