Okay the first thing you will feel the minute you get your hands on it is the urge to get one. I mean although you are familiar with most of the features already, it is still pretty insane. I personally felt, I finally got my hands on something as a kid I always imagined would be available in the future. Only obvious bad point way too overpriced. I mean £450 quid for the basic 16Gb non-3G model.
All the iPhone apps really come to life on the big iPad screen. My second favourite iPhone game (after iCopter, obviously) Flight Control was always meant to be played on the iPad. Other than that, new featured apps like Mail, iTunes, Pages, Keynote, etc. absolutely blew me away. The biggest miss of all was the absence of the USB slot. I think a must need for the next update.
The iPad is definitely a luxury more then a necessity. But if you are into gadgets and with no cash restraints, I recommend you get one.
