We've known since its unveiling in January that you're going to have to take the Motorola Xoom somewhere to be upgraded to LTE date. The question was where, and how. The answer(s)? Back to Motorola, via FedEx.
Verizon's posted up instructions on everything you should do before shipping your new Honeycomb tablet back to the mother ship for some LTE re-education, and it all it takes is three simple steps (one of them is optional) -- in a dozen or so parts.
The first step is backing up your user data and saving it locally onto a computer -- something that's a bit foreign in this day an age, but something we'd still recommend doing. (We're anal like that.)
The second (and optional, but very cool) step is to encrypt and hard-reset your Xoom. You've gotta have a full battery to do it. And if you leave it encrypted, you'll have to enter a password each time you log on. Or you can unencrypt, which also involves a hard-reset, but you'll restore all your date in the process. Time-consuming, but safe and cool.
The third step is to actually ship the device to Motorola via FedEx. You'll be provided a bubble pack -- wonder how long it'll take to get to you -- and then ship it off. And a week or so later, you'll get it back, LTE-enabled.