It already happened. Check your settings to see if it's turned on.
As suspected, my settings are correct. When I went to About Firefox I got the dialog.. downloading update 0 of 24.2MB downloaded. Seems like they still have work to do.
"An idealist is one who, on noticing that a rose smells better than a cabbage, concludes that it will also make better soup." - H.L. Mencken