It seems as though there are a few sizes coming out. I'm personally most interested in the 10" machines. A 10" LED backlit lcd display rocking 1024x600 res with one of those new atom cpu's just sounds so badass! Small enough to be hard to the core, but big enough to be able to enjoy websites without so much horizontal scrolling. Granted, most of the 8.9" screens are also 1024x600, i think 10" is the money ticket.
After reading everything i have, I will be leaning more towards the MSI Wind or Acer Aspire One OVER the Dell E. Who knows. I need a new pc. My shuttle box is getting closer to needing a replacement and i dont get on a pc at home nearly as much as i used to, so i feel one of these little bad boys will be more than plenty... I hope they start hitting shelves soon. B-Day coming up next month!

Nice site with good conglomeration of info.
http://www.umpcportal.com/