I don't see why this is still an issue. As it stands now, yes, you keep your unlimited data if you preorder. When you're going through the pre-order process, you have the option to select a data plan, and your Unlimited plan is the selected option, you then agree to the terms and conditions of extending your contract, and are then sent a confirmation email listing Unlimited Data as one of the features of the plan you just "signed" a contract for.
Granted, the contract doesn't go into effect until you receive and activate your device, but the contract you agreed to is for a plan with Unlimited Data, they can't just change that without going through the entire process again and making you select a new data package and agreeing to the updated terms and conditions. This would be extremely difficult to implement, and greatly complicate the process of activating a new phone even for users uninformed enough not to realize that they're losing their Unlimited Data. Besides, they couldn't implement it for those of us with existing 4G LTE smartphones, as the SIM itself is activated, and not the phone. I have a Razr, so I already have the microSIM, and can just pop it in and fire it up. Thus, they would have to use multiple methods to force people to do what you're suggesting.
There's also the issue that statements are pretty widespread that Verizon will allow you to keep it if you pre-order. And the fact that many reps in stores and on the phone are telling customers this. And that there is NOTHING to indicate that you may lose your data plan by the time the phone ships. If Verizon planned on forcing us to change even if you pre-order, they would already have issued a high-priority internal memo to prevent CS reps from telling customers blatant lies.
Verizon will have enough of a PR nightmare with this change as it is, they don't want to add a high-profile class action lawsuit to their plate. Personally, I think their hand was slightly forced, as they had to keep up with the other carriers on the GS3 before they had time to announce the new plans. Verizon implements changes for the worse all the time, but they do announce them at least 2 weeks in advance, so they couldn't just rush this on us the same day as the GS3 announcement. They allowed GS3 pre-orders because everyone else did, and didn't force you to change data plans as they hadn't announced the new pricing structure yet. Now that they have, they could feasibly change the preorder options to force pre-orders to change to a new plan going forward, which is why I submitted my order today, but I honestly don't see them doing even that.
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