I've done search after search, messed with color profiles, image color management, etc, but I still find that when I simply print screen and paste it in Adobe Photoshop CS3, I get a much lighter image. It even looks like it has less colors, or JPEG compression artefacts.
I've tried flipping between sRGB, Macintosh RGB modes etc. If I paste the screen capture in windows paint, it's absolutely fine. Any ideas?