Hehe, this is pretty funny. I've spent the last two days looking at them myself. I'll share what I know.
Right now is a pretty good time to buy. New models are coming out next month, that happen to not be that big of a difference, and the old models must go. Dell was just selling it's mini (with 4megs of ssd memory) for $199 but it's back up to $250. Still, you can find many for around $250.
Here is the important stuff to know - Nearly all of them use Intel's Atom CPU (1.6Ghz). It's somewhat revolutionary as far as power vs power consumption goes. They also all currently use Intel's chipset/motherboard.
The current netbooks out there are all roughly the same in performance. That is to say, they are not speed demons by a long shot. They are really designed for just checking email, surfing, maybe some light word processing. Much else, and it will bog down quickly. Don't even think about HD video or gaming beyond solitaire.
Nvidia plans to roll out a new chipset (same CPU) that is currently used in the macbook's which is much more powerful. It will allow HD video and some 3D. The current hangup is power consumption so they expect to have the first units out late summer.
If you can wait, and want more power, wait for the nvidia chipsets.
If you want something to just do light surfing and emailing etc., then now is a good time to pick up the Intel models.
You can google around, but I have yet to find a really good American site that reviews and compares all the current models. Because they all use the same cpu/screens etc, the only real big differences between them are as follows:
(SSD (Solid state) memory - this is used instead of a hard drive. It's essentially the memory in those usb sticks stacked together. Expect to get about 8GB with your netbook for $300 or less. You can get replacements that go up to 64GB, but they are pricy. The advantage to this is speed, almost instant boot up time, slightly smaller and lighter. You can also expect more reliability as these aren't susceptible to shock.
Hard drives - others come with normal laptop hard drives. These will take a little more power and will need spin up time. But the advantage is far more internal storage, usually 160GB.
Screen size - Some have 8.9 inch, others have 10", but they are almost all 1024x600 resolution.
Battery - You'll see 3 cell and 6 cell. It's the difference between 2.5 hours and 5 hours. 6 cell is also going to add a little bulk and weight.
Keyboards - This is the big one that the reviewers tend to focus on most. Many netbooks are despised for their ackwardly small keyboards. Others, like the Acer, Lenovo, and MSI are considered ok. But you have to accept that the keys will be small and scrunched, that's why you bought this device.
And remember that none of them come with internal dvd/or cd drives and never will. They just take up too much space.
As far as reliability there is nothing I have come across to suggest that there is anything inherent about netbooks to make them less reliable than the average laptop. They use mostly the same components, with a special focus on small and low power.
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