1. iPad (WiFi) has a maximum EVER limit of 16gb of flash. Other iPad' models MAX limits are 32Gb and 64GB. However with easily swappable and upgradable Micro SD cards the TAB's memory is in effect limited only to how much you buy.
2. Actual price of Tab after buying 16gb card is about $50 more (The Tab comes with either 16GB or 32GB internal, and can take up to a 32GB Micro SD card. Indeed Amazon are quoting 16GB is included in price, but until they go on sale, this is yet to be proved)
3. More apps with iPad.
4. iPad's display is bigger but as the Tab has a higher Pixel Density (169ppi), compared to the iPad's (132ppi), the Tab's screen is higher definition. And even if it were the same size, because of the the Tab's Pixel Density, it would still be better looking.
The only thing the Tab has over iPad is Flash 10.1.
and these few other minor points
512MB RAM (iPad 256Mb)
Front Facing Camera 1.3MP (iPad None)
Rear Facing Camera 3.15MP (with LED Flash) (iPad None)
Built in GPS (iPad Wifi None)
Bluetooth 3.0 (iPad Bluetooth 2.1)
GeoTagging (iPad None)
Stereo Speakers (iPad Single Mono)
Tethering (iPad None)
Multi-Tasking (not currectly available, but due in iPad 4.2iOS)
Swype Text Input (iPad None)
Text Input Vibration (iPad None)