To apply color to text in OpenOffice.org Writer, you select the text, then click and hold down on a text color icon, find the color you want, and click the color. (Note that right now before the color is applied, the color under the A of the font color icon is white.)
That color is applied to the text, of course. Note that now the line under the A font color icon is red, the most recently applied color. Even though no red text is selected.
Now if I select some more text and just click the font color icon, rather than having to bring up the palette and pick the color again, like before, I get the most recently applied font color (the one shown in the line under the font color icon).
Ditto with the highlighting icon and the fill icon.
That is the way it works in Word, I understand, and that's how it now works in Writer 2.3. It does NOT work this way in Calc or Impress/Draw, though I would have to assume that's coming.
I wanted to point that out because I've heard complaints about how the text color icon (or text highlight icon) used to show the color of the currently selected text, not the color that you most recently applied. One could make an argument either way, but apparently the OpenOffice PTB (powers that be) decided to switch it to match Word. I must admit that I like it the new way, myself.
So -- two things here. One, that the OpenOffice folks listened to input from users, and two, that the font colors work this way in 2.3.