Turning Internet Explorer off
The proposal details a lot of the questions and uncertainties raised in our comments' sections. For instance, it explains what it means not to have Internet Explorer installed - which Microsoft calls "turned off"; "namely its browser frame window and menus (user interface), will not be accessible and will not otherwise launch programmatically".
In addition, the only way Internet Explorer can be re-installed is through user action aimed specifically at installing Internet Explorer. There will be no icons, shortcuts, or links within Windows or other Microsoft products that will initiate an IE download, and Microsoft will not use Windows Update to install IE; only when IE is turned on will WU update IE. Microsoft does note, obviously, that Trident will continue to be updated through WU.
A very important additional note (at least, for me) is that other applications will not be able to call upon Internet Explorer's user interface; in other words, applications with Trident hardcoded into them will still be able to work. This sounds like a reasonable compromise to me.
Of course, OEMs will be free to install and set as default any browser they wish. Microsoft specifically says that it "shall not retaliate against any OEM for developing, using, distributing, promoting or supporting software that competes with Microsoft web browsers, in particular by altering Microsoft's commercial relations with that OEM, or by withholding Consideration". OEMs will be able to block the browser ballot from appearing on their computers.
The ballot screen
Contrary to previous assertions, the browser ballot screen will not be limited to Windows 7; Windows Vista and Windows XP users will get it too. It will be delivered to all current and future users of Windows XP/Vista/7 through Windows Update (rated "Important" for Vista/7 users, "High Priority" for XP users). XP and Vista users will get it between three and six months after the EC's ruling in Opera's antitrust case. Future Windows 7 users will get the ballot screen on release, or within two weeks of the EC's ruling.
So, what will the actual ballot screen look like? Microsoft goes into insanely great detail to cover this. Each web browser listed will have two links: an install link which will automatically download a local installation package form a vendor-managed server, and and information link which will connect to a vendor-managed information page. The ballot screen will present browsers on a horizontal line in an "unbiased way" as icons. Opera actually complained about the use of icons, stating that it provides an unfair advantage to IE, as people will recognise the icon more easily.
It will include the ten most popular browsers that run on Windows with a usage share of 0.5% or more in Europe, as measured by an agreed-upon source. These figures will be updated semi-annually. A browser must be actively offered by its vendor to be included. Different versions will not be taken into account; usage share of different versions of the same browser will be added up. The five most popular browsers will be displayed more prominently. The information on the ballot screen will be updated monthly. Also, non-Internet Explorer browsers based on Trident are not allowed to be included.
On a very interesting note, Microsoft will ensure that all the Windows APIs which rely on Internet Explorer will be "disclosed in a complete, accurate and timely manner", so that other browser makers will not be at a competitive disadvantage. This must mean that Windows Update, which on XP still requires Internet Explorer, will probably be made to work with other browsers too. Also a welcome requirement: browser vendors may not include additional software in their installation packages - so no toolbars or other forms of nagware.