Yes, the iPad will display your raw files however it's not much cop for editing shots.
I have set my camera up to produce a raw and a small (fine) jpg. Each time I take a shot the camera will wirelessly transfer a copy of the jpg (about a 5mb file) to the iPad using an sd Eye-Fi card. This takes about 5 seconds a shot. The iPad can then be used to view photos on the fly. You can edit the jpgs but it's not really worth it as I just process the RAWs I want to keep when I'm back home.
The ipads resolution is only 1024x768 so anything other than a small jpg is a waste of time, however I find being able to view shots instantly and being able to pass the iPad around to friends absolutely invaluable. It's so much easier to determine which shots are keepers when youre in the field from the iPads superb display rather than the back of the camera.
Anyway, there's a lot more to the iPad than just messing about with photos. I do not regret buying mine one bit, its totally replaced my laptop.