I just came from a Verizon store. I asked about a Galaxy Note 2 for my fiancee's line, which had a dumbphone. I asked the rep if my fiancee didn't like the phone, could I just put this Thunderbolt on her line and transfer the Note to mine? She said yes, but you might have to come here to do that because of the 4G sim cards. So, as I'm going through with the sale, she gets set to open the Note to insert the sim card and I say, can we just switch them now, while you have that open? She looked at me kind of strange and said sure, lets go to a real computer (all this was happening on an iPad). This process took about 10 minutes and she finally says "wanting to keep your unlimited. eh?" and I said "If that's the way that works out, great!" So, I have a brand spankin' new Note on an unlimited line. She has my TB now with a 2GB plan but the odds of her going over are really slim. So, yeah! it works!