Either way seems ominous to me from a security perspective. As an attacker, I will either detect your nice new wireless thumb drive as a plug-and-play-aware piece of hardware, or I will see it broadcasting via some 802.11 compatible wireless protocol. Now I'm going to assume that the security implications of such a device were well thought out by Touch360, but then again, I don't imagine that the target market is Enterprise IT. Consumers generally don't care much for security, because they don't generally have the understanding or wherewithal to properly protect their data. And given that people seem to leave thumb drives around like they do pennies, any technology that can further enable data theft is obviously a bad thing.
Using Bluetooth for data communication would certainly appease my security concerns, but not many laptops nowadays have built-in Bluetooth, and a Bluetooth-enabled USB key would certainly cost more. And if it is Bluetooth, hopefully the manufacturer sets the pairing key to something other than 0000. It's bad enough that every time I do a Bluetooth scan on my phone, I seemingly detect 15 Bluetooth-enabled keyboards, mice, computers, and headsets.
Now that I'm done complaining about this new product genre, I'd love to try one out!!!!!! Touch360, if you're reading this, feel free to send me a few free units for demo! I'll ship them to the first readers who speak up here and voice their interest.