As I assume most of you are painfully aware, Verizon is doing away with their grandfathered unlimited data plans. Those wishing to keep their unlimited data will need to act fast. According to a Verizon rep I spoke with, customers who renew their contracts by August 1st will be able to keep their unlimited data, even when upgrading to a 4G phone. UPDATED: Customers need to upgrade by the 28th of this month (June). After June 28th, customers who want to keep unlimited data will have to buy thier phone at the full retail price.
I can personally confirm the upgrading to a 4G phone is not an issue in keeping unlimited data as I have just preordered my Samsung Galaxy SIII.
If you have unlimited data and are eligible for an upgrade/renewal, I suggest you jump at this grace period.