What we haven't heard many leaks about is how this new Start Button will work. While sources have emphasized that the Start Button won't work the way the current Windows Start Button does -- by opening up a Start Menu -- that's about all we've heard.
I've been trying to glean details on how the new Start Button will work. Here's what I've heard from one of my primary Windows Blue sources, who has been dead-on about all the Blue information he's shared.
The new Start Button supposedly will look just like the Start Button that is currently part of the Charms menu in Windows 8: An angled, stylized window (like the one at the top of this post). It likely will be turned on by default, but can be turned off for those who like the Start Button-free design that debuted with Windows 8.
This new button will sit on the taskbar in Windows 8.1, in the same place and in the same way that the "old"/current Start Button does with Windows 7.
When users are on the Start Screen or inside of a Metro-Style/Windows Store app, according to my source, the new Start Button won't be visible. It only will become visible if/when a user moves the mouse to the bottom left corner. Instead of seeing the thumbnail of apps that Windows 8 users see when the mouse over the left corner, they'll supposedly see the new Start Button instead.
There's also going to be an "All Apps" view that users will have the option to use instead of the tiled interface, my source said. This is the same All Apps view that users can get in Windows 8 now when they bring up the app bar and select "All Apps." In Windows Blue -- as previous leaked builds have shown -- users can get to it by swiping up on the Start Screen. (The screen shot above of the All Apps view is courtesy of the Windows SuperSite.)
But Microsoft plans to allow users to show "All Apps" by default for those who don't want the tiled interface, my source said. In this view, selecting the Start Button will bring up the Start Screen with a list of apps with icons, and no tiles. Users will be able to arrange the icons by usage, allowing the most commonly used apps to be first. This view is the closest users will get to the Windows 7 Start Menu, even though it will be full-screen, instead of a list.
Boot-straight-to-desktop is in the Windows Blue Milestone Preview builds, too, my source confirmed. And it supposedly works just like it sounds: Users can opt to see the Desktop, and not the Metro-Style Start Screen when their PCs/tablets start up. Clicking the Start Button in this view takes users to the Metro Style Start Screen, even though users start on the desktop.
There's one more interesting UI tweak that may come with Blue, my source said. Microsoft is expected to allow users to use the same background across both the Metro Start Screen and the Desktop with Blue. The idea is by doing so, moving between the two environments would feel less jarring.
I asked Microsoft officials if they wanted to comment on my source's information. No word back so far, but I'm not holding my breath.
Update: A Microsoft official said the company had no comment on this post.
Update No. 2: Windows SuperSite's Paul Thurrott has some screen shots of the new Start Button and the common desktop wallpaper from a recent Blue preview build. (With his permission, I'm including one of these screen shots in my post above.) Thurrott said in the upcoming preview (at least), the new Start cannot be turned off. But bottom line: Looks like my source was largely right.