Breadcrumbs is a feature I've been wanting to implement for quite a long time. In b2evo 4, I started adding them to the admin interface...
I realized one of the reasons we failed to implement them properly before is because we tried to tie them to the navigation. In theory it makes complete sense that the breadcrumb path follows the navigation. In practice however, it doesn't! One of the reasons for this is that b2evo's admin has 2 main dimensions of navigation:
Navigate through features, sub-features, etc.
Navigate from one blog to the next
I believe that the breadcrumb path doesn't make sense until it integrates the second dimension into the first at some point... which has to be an arbitrary point, but nonetheless... The result is what you can see on the first image above. What do you think?
I think it works pretty well, but I can take no credit: I just followed the instructions from Steve Krug's Don't Make Me Think by the letter ;) (page 78)
I must admit though, there's one area that isn't crystal clear in the book and I can't quite make my mind up:
In the second screenshot, there are basically 2 options for the breadcrumb path:
The first one describes the current page better than the second. However, the second more accurately reflects the navigational path taken to get here ("All items" is the default view/tab for "Contents").