19 June 2012iMore:
With iOS 6, the translucent and hidden states are still there, as is the black state, but the light gray default has been replaced by a color that’s tinted based on the that of the menu bar — or more exactly, a color averaged from the bottom row of menu bar pixels. Developer Simon Blommegård ran several tests and determined if, for example, you entire menu bar was yellow but the bottom row of pixels was half red and half blue, the status bar would be tinted with a purple hue.
I don’t like the new custom-coloured status bars, mainly because it makes the text in the bar harder to read1, as the traditional contrast of gray-on-black is lost. This is my number-one complaint with iOS 6, and I sincerely hope the ‘feature’ is removed by final release.
1 For example, see this comparison image by iMore. The white-on-blue status bar is difficult to read quickly, as the colours are too similar in contrast.