That's just the regular Wi-Fi model; Wi-Fi + 3G ones aren't out until "late April." Both versions will be available for pre-order (either for shipping, or for in-store pickup at an Apple Retail Store) starting next Friday, March 12.
Note that the shipping iPad does not have a camera. (Not that any sane person expected Apple to add a camera, but anyway.)
Also, the iBooks app (and yes, it's an app, not bundled with the iPad) will be available from the App Store on April 3. No word yet on whether the iPad version of iWork will also be available that day.