I've been using an Eee PC 1000H for a couple of months now and it's surpassed my expectations. The battery on my big old Dell D820 has been dying for some time and I got fed up of lugging the thing across town to Starbucks. So the Eee PC has been a diminutive godsend.
As well as the obvious surfing and word processing, I've found it's good for light programming and I've got a huge amount of work done in a variety of Edinburgh cafés (this morning, a Starbucks table away from the novelist Alexander McCall Smith). With over four hours of battery life, it's never yet run out of juice on me - my concentration usually gives up the ghost well before that.
I'm finding the keyboard very usable, especially compared with my old Eee PC 701. The 10" screen is less restrictive than you'd think, in fact quite relaxing after working with a 1650x1050 15" screen.
Poor old D820, I think it's feeling neglected. I'm not sure what kind of notebook my next 'main' machine is going to be, but I'm not going to back to 3kg monsters.
In summary, if you're thinking of getting a netbook, you're unlikely to regret purchasing a 1000H, or, probably, whatever model Asus replaces it with.