Ordered the 16GB-3G version on launch day and being very curious and a little bored, I decided to do a mock up based on the exact size of the iPad (height & width anyway, the thickness is probably off a bit)
The screen is actually smaller then I expected. The bezel around the screen is quite big, but makes sense once you hold it because of where your thumb is. If the bezel was thinner, your thumb/fingers would be on the screen when holding it and Im sure would cause all sort of problems with multi-touch.
It feels very comfortable to use when laying down with your knees folded so you can rest it on your thighs...but with your legs straight, you have to hold it up and naturally have to use both hands. My laptop did allow me to just use one hand for the trackpad and have the other hand free for the TV remote or a drink, guess that will take some adjustment. Same with using it at a desk...seems like the stand is a must have or you can prop it between your stomach and the desk edge if you are slouching back.