2011/9/12 Kévin PEIGNOT
<winniemiel05@xxxxxxxxx>
For battery low, icon become red i remenber (it did few times ago). It's red when it's urgent, blue for notifications.
I think it's a sort of must be the blue icon for calendars ;). Maybe for 12.04 since Thunderbird+Lightning is just new in Ubuntu, and it's integration isn't complete actually.
The powercog (or whatever it's called, last icon, top-right) is also painted red when a reboot is required!
Blue (reminder) / Red (urgent) is a great idea, as very few people have dyschromatopsia on these colors (normally it's red-green (frequent) or blue-yellow (less frequent). Having both is pretty rare and total achromatopsia is ~1:33000).