Thanks, but I’m not using CSS (and being a total newbie it might have belonged there all along…). I was using the color picker palette thing and saved it. It shows in the preview, but not in the actual live blog.
It looks like setting on the Appearance → Header page for the site title is overriding the color being set in the colors tool. Try going to Appearance → Header, find the “Text Color” option, click to select a color, click the Default button, and save changes. Does that fix it?