Yes, VZW is still offering unlimited data for $30 if you go pre-paid. Scroll to the near bottom of the page below.
Plans - Verizon Wireless
Verizon can still afford to offer unlimited data, despite what they and other carriers will tell you. They'll want to offer it to at least some of their customers still. They know that most customers want to get a phone at a discounted price and stay on contract with them. They dislike having prepaid customers obviously and need to throw them a bone, albeit a very juicy bone.
But, why do they need to throw a bone to their prepaid customers?
For one thing, prepaid customers will pay full retail price for a smartphone which can be $500+, getting no contractual discount. Also, prepaid customers get slightly less coverage than postpaid customers. I believe they cannot roam in remote parts of the U.S where VZW doesn't service. Whereas postpaid customers can roam onto regional carriers like U.S Cellular and Thumb Cellular. Finally, their monthly bill is slighter higher than a postpaid account for the same plan, features, etc.