You would need to get an Eye-Fi card, either a Pro card or a connect X2.
The nice thing about it is that you don’t need to Jailbreak t
he iPad to create an Ad-Hoc wireless network. The new Eye-Fi card will do this for you and act as a router. (well, technically speaking it is not actually a router, but you get the point).
Sadly for mid range dSLRS (like the D300 that I shoot) it does not appear that Eye-Fi are going to release a CF version soon (or ever).
How To Tether Your Camera To An Ipad Without Jailbreaking via Fstoppers