Cyanogenmod stopped being blue The icons changed to a green scheme instead of the normal blue scheme, and it persists even after reboot. The autocomplete text is yellow now, as is the browser loading bar.  What happened??

This screenshot is from a while ago, when I was using a different launcher, but it shows how the colours were until yesterday. (There's also some unrelated background corruption.)



Now the Wi-Fi and cell and messaging and browser icons are green:



I tried reflashing the same version of CM7, and it's still green:



I don't care too much about the color, but I don't know how this could have happened and wonder if it indicates some kind of corruption of the phone's Flash, etc?
The colours aren't the only difference. Your second screenshot also has a dark background to each shortcut's label, and a different graphic for the tray at the bottom. The combination of graphical changes to the launcher, changes to SystemUI, and different-coloured icons for system apps like the browser, makes me say the second screenshot is of a different version of Cyanogenmod, or a different ROM completely.

Could you or someone else have flashed a new ROM onto your phone? If you're not sure, go into the Settings app, click About device and read the version information on that screen.