The fanboy blog Apple.pro just posted a photo of what looks to be a shipping manifest. Their inside source reports that it is from the cargo terminal at the Chengdu International Airport.
I cannot read Chinese (and Google Translate isn't helping much), but you can see that it says UPS. According to Apple.pro, the shipper is Chengdu branch of Foxconn,the current manufacturer. If the photo is to be believed, this shipment is traveling to Chicago (where UPS has their main hub), Los Angeles, and NYC.
So why 3 locations? I don't know about you, but I think this is a distribution plan, not a shipping manifest. There are too many dated entries on this one sheet for it to be just single shipment. I really think we're looking at Apple's plan to preposition the iPad 3 for the launch that is supposed to happen next week. This would tie in closely with the past leaks, including the iPad 3 shell, the cable sub-assemblies that leaked in the UK, and the hi-res screen which appeared a couple weeks back.
But there's a problem with the launch. Note that it is only rumored to be happening next week; I haven't heard that Apple has sent out the invites yet. That's going to make it kind hard to have launch event; without any press there, there won't be anyone to drool over the new iPad.