a whopping 85 MBs and with a basic service DSL, got done downloading and installing just a little over two hours. Ouch!
If you have dial-up, this might test your patience. There are some changes: there's a pop-up blocker (I already have the Google toolbar), a manage add-on thing-a-jig, an alert at start-up that let's you know if your security softwares are off or on, and maybe some other things not yet noticeable.