Were you using a non-standard colour profile prior to installing Snow Leopard?
The default profile (e.g. 'Color LCD' on MacBook Pros) is set to have a white point of 6500K, which is comparable to the warmth of sunlight.
If you were using a colour profile with a native white point on any LED-backlit Mac (any MacBook Pro after June 2007, for example) your screen would've been very white, or relatively blue.
Snow Leopard would've set your system to the standard colour profile (with the 6500K white point), which would make your grey title bars appear slightly 'brown', actually yellow.
Your eyes will get used to the new (normal) setting, so don't worry about it.
That's why the screen shot looks the same to anyone who looks at it. 😉