I'm honestly not trying to jump the gun here.. but I felt it necessary to really take a closer look at WE's breadcrumb.
Sorry about the length - I wanted to illustrate some of the finer, and possibly less-noticed, aspects in their implementation.
It's dangerous to go alone. Take this!
Usability thoughts from the Win 7 WE breadcrumb...
- When clicking an arrow the focused folder, whose children are being listed, adopts the pressed state - this is a great visual aid in helping the user understand where the items in the displayed list reside.
- After clicking an arrow to display the drop-down list, the breadcrumbs behave similarly to the application's main menu in that the displayed drop-down list changes when the user hovers the mouse cursor over a different level or category. This is a time-saver - especially when the user's first arrow selection is the wrong one.
- Combining the previous two items... The WE breadcrumb requires clicking on the arrow to initially show the drop-down list, but because after that the focused folder acts like the arrow itself the user only needs to hover over a different level instead of an arrow and its much smaller target area to change drop-down lists.
- By using F6 it is possible for keyboard users to focus the breadcrumb, use left/right to select a level, down to show drop-down list, Esc to hide it, and Enter to browse to the selected location. The user can focus an item using type-ahead find, but a selection is never automatically made which is probably due to the fact they use a list control for the drop-down list.
However WE's implementation also has shortcomings that maybe you can improve upon...
- If the list cannot fit on the screen it is drawn over top of the breadcrumb, making it impossible to do many of those nice things above, like hover over what is now underneath the drop-down list. I'm not sure how XY could improve upon this aspect of things - maybe introduce the revolutionary Vertical Breadcrumb where this wouldn't be an issue?

- Once the drop-down list is shown and focused the user must use Esc to close it before they can change levels. This doesn't make much sense to me since left/right don't seem to do anything when browsing the drop-down list.
Brainstorm... or brain fart?
- If you don't much care for the hovering aspect, and feel a click to hide the menu to reach right-of-focus levels is acceptable, then I wonder if it would make sense to attempt to position the menu such that the default menu item falls near where it is on the breadcrumb, as shown below. This way the user's cursor is closer to the current item instead of the lexicographically first item. For me this makes sense because I am often jumping to folders near the current one. I realize this type of positioning may be a bit too exotic and to be perfectly honest I feel the hovering is a much better feature when it comes to usability, but I'm just throwing this out there.

- Imaging that the user has just clicked the arrow to the right of 'A'.
- breadcrumb-side-menu.png (30.08 KiB) Viewed 1765 times
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