A lot of people, including myself, had a hard time deciding whether to preorder a WiFi only iPad or a 4G iPad. In the end I felt that the 4G was not right for me because I mainly use the iPad at home and can tether it to my unlimited data phone if the need arises. For those still on the fence, I found an article from gizmodo that lays out the true cost of having 4G. I thought I'd pass it along: :http://gizmodo.com/5891064/how-much-more-the-ipads-superfast-4g-lte-data-will-cost-you-updated Here is some data from the article about file sizes: AT&T File-Size Estimates 1 App/Game (non-Retina): 4MB 1 App/Game (Retina): 8MB 1 hour of YouTube streaming: 120MB 1 hour of Netflix streaming: 306MB They also mention that pictures and apps are much larger because of the HD screen. This could make using the 4G iPad a lot more costly than you expected.