The best selection really depends on what you need; although most of the specs are very similar between the netbooks, there are some differences, such as hard drive space, built in overclocking potential, screen size, and 3G service.
The MSI wind, in my opinion, offers some of the best performance of the netbooks, as its newest bios revision enables semi automatic overclocking on AC power-- this means that the processor can run at up to 1.9 ghz while the laptop is plugged in, which is quite nice if you need a little bit of extra power for a heavier application or game. The Wind also has the added benefit of modifiability; it is possible to upgrade the RAM without voiding the warranty, and the aforementioned overclocking feature is also permitted by the warranty. I personally recently bought a wind, and so far have been very happy with it. However, the Wind does not come in a 3G variety, and has to depend on wifi for internet connectivity, also, it uses a more conventional Hard Drive, which, while providing much more storage and superior write speeds to a SSD, is also slightly more vulnerable to impact damage.

After reading through the tech specs, I found that the guts are almost identical. The only real difference is in the look which is a matter of personal taste.

Here's another Netbook (HP Mini 1000) that's getting decent press that you may want to consider. I've heard the keyboard is better than most....

If price is a factor, try the 3K Razorbook 400 mini notebook. Only $250 MSRP. also comes in different colors.

I've tried all of those you've mentioned. I like the Asus Eee PC 1000 the best. You might also consider the Samsung NC10. I would rate it slightly higher then the Asus.