When prompted on the Wirefly site at checkout, there is no indication that the data plan will be any higher than what you already have ($30 unlimited). In fact, it says your plan will stay the same. I suspect everyone has been freaking out over LTE pricing prematurely (it won't change until summer, maybe with the Bionic's release), but I expect we will find out for sure with an official VZW announcement today.
The real question is whether to buy it from Best Buy since I pre-ordered already (and risk paying $50 too much if they overcharge, which BB likes to do), wait to see what VZW will charge (and risk that my store will run out or charge the same as BB), or pull the trigger on Wirefly today for $200. I haven't decided what to do yet. Is there any reason NOT to buy from Wirefly? I'm not worried about double ETFs since I'm not going to be canceling my contract at all for any reason. The only thing I can think of is I will get it Thursday afternoon at the very earliest instead of the morning. The key is whether VZW stores will charge $200, $250, or $300, and whether there will be any instant or mail-in rebate. Hopefully we find this out this morning from VZW.