Personally, I prefer to relocate the element of surprise such that it falls after the delivery of gift.
The wife looks briefly away from the screen to profusely thank me for the e-gift voucher. A couple of clicks, and... WHAM! Goatse!
Retina displays did not exist in phones before the iPhone 4
Your earlier quote of "I'm not just talking minor megapixel or processor upgrades, but something game changing" seems churlish, given you are now talking about minor display density increases.
Frankly, the increased screen size of the androids with a corresponding *reduction* in dpi was a bigger innovation than the high-density display of the iPhone 4. Unseated the iPhone from #1 . Game-changing, no?
In the realm of scientific observation, luck is granted only to those who are prepared. - Louis Pasteur