Occurs in (at least) WinXP x64, Vista x86 and Linux (run under WINE) and results in the discoloration of the scoreboard.
This can be fixed by turning cl_gammaramp off (or gamma ramp in the advanced multiplayer options) which will cause the game to be darker.
So basicly people are going to start having this problem at the end of next month if it isn't resolved (no idea if its an issue with NS or some driver/OS issue) or made clear that gamma ramp needs to be checked off.
If anyone is running Vista with an ATI card it would be helpful to know if it has the same problem.
First brought up in this thread.
cl_gammaramp 1

cl_gammaramp 0