The Duo is a Niche product, and while sure not to be anyone's cup of tea there are a number of people who enjoy the netbook-tablet concept.
Unfortunately, what the netbook-tablet isn't good at yet is what most people expect out of it. People want something that is "An iPad but a computer." Well an iPad is an iPad for a reason, at least for now. We've had lots of touchscreen computers for years and they're all niche devices.
What makes the Duo (And it's lenovo & Gigabyte sisters, and arguably the ASUS half-sisters [I say half due to the resistive touchscreens]) so appealing to a small set of people is the fact it IS a notebook, but if you want to do light browsing or curl up somewhere for a reading/youtube session you have a slightly improved level of portability.
Anyone that expects Dell or Lenovo to in 6 months make an inside-Windows interface even CLOSE to the iPad in terms of usability may be an idiot. It would be GREAT, don't get me wrong, but these mini-tablets are all going to be 'mee-too' devices with a half-assed interface for a while. They -do- still have some dang good uses however.
(Note I left out the HP Slate, which takes everything bad about the iPad and mixes it with everything bad about the Netbook-tablet class. Where the hell is -that- on this list?)