Source: iPad (Third-Generation) Unboxing + Comparison Photos — a set on Flickr

Charles Starrett writes:

[…] the differences in packaging between the new iPad and the iPad 2 are small, with a different background image for the device, an iCloud badge on the bottom of the box, and the expected changes in the labels on the rear. Inside, the changes are similarly minor, with different, slightly more flimsy SIM card removal tool—included only with Wi-Fi + 4G models—being the most noteworthy difference. 

My favourite photo of the set is probably the one I chose for this entry, displaying all three iPad generations.