Not at the moment you won't.
The download link doesn't seem to be working. :'(
I guess it's because it very busy with people downloading the new build.
It would be better if you uninstalled the old version first, Michelle, then delete the Mozilla.org folder in your Program Files. In that order. That way you will get a clean install, rather than possibly leaving some odd bits behind. Download the new version first, of course! You won't lose your Bookmarks or other settings, as these are stored elsewhere on your hard drive.
