I just got a refurbished dell mini (could have been me on that train) and love it. There are a few trade off's, but that's the price for the smaller machines.

I would say you need to figure out what's important for you. I went with a small screen, but wanted one with higher resolution (at least 1024 x 768). Most netbooks don't go to 768, so you will have to do more scrolling.

The screen is small, and the keyboard is smaller on mine. Given the choice I think a full size keyboard would have been better, but there would be a tradeoff in size. I just took it for a long weekend trip, and after using just it for a day or two the keyboard was much easier to use (key spacing really does matter if you can type).

Broadband can either be built in which will probably limit you to one carrier, or you can use a usb dongle for it, or you can go either Verizon or Sprint for their MiFi device. I went MiFi for access, as there may be times I want to use it for other devices or multiple devices, and for the most part there's good coverage from White Plains to Grand Central and from Grand Central to Fairfield on Metro North. I like that nothing is hanging off the netbook which I'll certainly break off at some point.

Battery life if key for me, and I was lucky mine had the extended battery that sticks out the back a bit, adding a bit of weight too. I think if I was to let it go all the way down I could easily get seven hours of life from it.

I do find the multi function trackpad fustrating. That's more of a user interface issue, I just don't have the hang of zooming in and out and scrolling and the rest with it yet. To be fair, I could disable those features, but want to spend more time trying first.

If you plan to do a ton of camera uploads to it, you may want one with the memory card reader built in. If you want to do presentations with it and don't want to carry adapter cables, you may want one with VGA out. If you want to attach lots of things to it at once when home, say a printer, a keyboard, a mouse, etc, you may want extra usb ports.

Go someplace where you can play with the keyboard for a few minutes, see the screens of the ones you are looking at side by side, etc.

Pay attention as already mentioned to the amout of memory they come with or can be added, make sure it fits your needs.