Typically, on any black-colored iOS device, the respring or reboot screen is going to be black with a white Apple logo; and conversely, any white-colored iOS device will have a white respring or reboot screen with a black Apple logo.
Although some people may like the small variance Apple has given their devices, others may like to have the option to switch it up for themselves.
For those people, a new jailbreak tweak called InvertRespring will invert the respring and reboot screen's background and Apple logo colors to their opposites, and is now available for free in Cydia.