I'm still using an Eee 901 I bought last year, upgraded with a 16GB SSD and 2GB of RAM. It is running Windows 7 Professional and does a perfectly adequate job for me when I need cheap, light, and long-lasting. I didn't replace it this year for a few reasons - first, I'm watching the company expenses as carefully as I can, but more importantly there's nothing really new or worthy this year in the netbook category. Except that everyone got into it.
2010 will change that some with the nVidia Ion platform and Intel's Pine Trail Atom. Now, performance is just on the edge of low-end laptops (enough for HD video) and battery life is 20+ percent better. It's viable to get 10 hours of life from a 6-cell battery. The 9" form factor I have in my 901 turned out to be kind of a dead-end (as did the 7" before) - what's making the platform now are the 10" and 12" screens. They allow space for keyboards that are much more usable (the letter keys are within a couple percent of full-size and the other keys are a little shrunken to make up for it - 12" models usually have a real keyboard). The only other dead-end in most models was the use of SSD - I for one will miss that a lot since it made them more rugged.
The model I consider next year will have a 1366x768 screen (the one I have now is 1024x600), likely a 160 or 250GB hard drive, 1GB of RAM standard, and it'll probably include Windows 7 Starter. Not bad for a netbook. Double the RAM and upgrade to Windows 7 Pro, and we're looking at a real laptop for under $400 that'll run for a full work day and then some on batteries.
And you wonder why Apple's pretty much the only PC maker making big profits. All that margin the other companies used to have vanished in the netbook frenzy. Which, by the way, is also why Apple doesn't play in that segment.