When Verizon introduced its shared data plans last year, it simultaneously stopped allowing customers with unlimited data plans to upgrade to new devices at a discounted rate and hold on to their bottomless plan, forcing them to buy hardware at full retail price instead. Verizon has shown no signs of budging from this policy since, but apparently that's not the case for the big red carrier's website this weekend.
According to reports from several Verizon customers, Android Central and Droid-Life, Verizon's website is currently allowing unlimited data customers to upgrade to a new device at a subsidized rate while retaining their unlimited plan. That means that subscribers can go through the normal upgrade process to pick up a shiny new piece of hardware, including the LG G2 and Samsung Galaxy Note 3, at a two-year contract price and hold on to that bottomless bucket of data that they've been clinging to for so long.
Verizon hasn't commented on this situation, so it's not clear exactly what's going on here. Considering that Verizon hasn't shown any signs of changing its stance on unlimited data, I wouldn't be surprised if this were some sort of website glitch rather than a special promotion or new policy from Ol' Red. That doesn't mean that you Verizon subscribers with unlimited data can't try to take advantage of it, though. Just keep in mind that your carrier may decide to fix the glitch and possibly even cancel orders at any moment. Be sure to give us a shout if you're able to upgrade with an unlimited data plan intact!
UPDATE: According to Droid-Life, the bug or whatever it was that was allowing unlimited data plan upgrades has been taken care of by Verizon, meaning that unlimited data customers will lose their grandfathered plan when attempting to purchase a subsidized device. Verizon still hasn't explained what happened or if those subscribers that took advantage of the loophole will actually get to keep their subsidized device and unlimited plan, but hopefully we'll hear more soon. Stay tuned.