I use my Ipad all the time.
heres a few of the apps i use on my Ipad 1
Nik Snapseed - a very simple, easy to use image editor - great for "playing" with images
Filterstorm Pro - a very very good image editor, allows you to rapidly sort images, add captions, crop, resize, basic PP and then FTP the images out - so its great for Photojournalists, and people who need a way to caption images, then FTP them.
Sunseeker - an app that shows you where the sun will be - i use it for picking where im going to shoot during Car Rallys, plug the date in, line the paper stage maps up right, and you can see where the sun will be at whatever time
Google Maps - for finding where im going
Foliobook - a portfolio app - not too bad, sometimes a bit laggy, but the images look good.
Strobox - Lighting diagram creator
Ibooks - got all my Camera manuals loaded into it, along with equipment that work owns, that i may have to use occasionally
Adobe Ideas - a drawing/notetaking app - also allows you to import photos and draw over the top of them, handy for showing someone what PP to do (i use it all the time with my wife, she emails me a pic, i scribble on it, then send it back)
Dropbox - a Cloud storage system, i can upload stuff to it, and access it from any computer with an internet connection, i also have a linked folder that my wife can see, which allows us to share files instantly.
One of the guys at work is using Shuttersnitch with an Eyefi card.
basically he shoots with a 1DSmk3 - Raw to the CF card and small Jpeg to the Eyefi SD card - which sends the image via wifi to the ipad and Shuttersnitch, and allows him to keep shooting, while the stylist sits down looking at the ipad rather than over his shoulder at the back of the camera.
Hope this helps
I also love FruitNinja HD, FlightCtrlHD, Angry Birds and NOVA2 to keep me occupied.
there is a few of us at work with Ipads, Iphones and Ipod touches who play Nova as a multiplayer game via wifi or bluetooth