Really quick review - really, really like it. Glad I have it.
Longer review: The iPad on first glance looks like an oversized iPhone. I have a problem (still) with the extremely spaced out grid of applications - I would rather see more icons on the screen (or have a little bit of control over sizing and placement).
The screen is bright and beautiful. Text is clear, colors are saturated and its a joy to look at. I have done some web-browsing on it, and read books using the Kindle for iPad application.
If someone came up to me and asked whether they should get a Kindle device or an iPad - I'd first ask if spending twice as much mattered to them, but then direct them towards an iPad. The greater flexibility of the backlit screen for reading is a winner. When we visit my parents we often are driving back in the evening. I usually am the passenger. I often read on the way back - I have read physical books, on a succession of Palm devices, on my Kindle (1 and 2), and on my iPhone. Reading on the iPad is a hands-down winner. Clear text, quick page transitions, and a backlight. I don't need a flashlight to read at night anymore.
My one (slight) downside is the weight. 1.5 pounds does weigh at you a little. My father, recovering from Rotator Cuff surgery, had to put it down because it was straining a bit. I'm recovering from an RSI flareup in the wrists and hands, and I can feel the strain also. (I prop it up a lot)
However, my mother and sister were enamored of it. Or at least, enamored of the games: my sister played Plants vs. Zombies, and my mother played TriTowers Solitaire for quite a while, and I thought we'd have to peel the iPads away from them before we left.
We did try to play a game of Scrabble - that went badly. While the 2 person game T and I played at home worked well, the 4 person game we tried at my parents house didn't. We had 3 iPhones and 1 iPod Touch running Tile Rack, and the iPad hosting the game. We kept losing players intermittently, and finally gave it up as a no-go.
I have been hoping for an Apple Tablet (or, more exactly, a good, functional, touch-based tablet) for years. I had wanted a bigger Newton back in the day. I've owned a Compaq tablet (slow, and the pen-based input bugged me). The iPad makes me a happy geek.
I'm not sure if I'm going to be envious of the 3G model later. I'm thinking not. (But, the MiFi's look tempting...)