Decide not to re-invent the wheel.
Extend observablecollection, Set up transitions and you should be good to go. Dr. WPF had the Breadcrumbcontrol designed in 2007, yeah, about 5 years ago. Many of them have built their breadcrumbs using this.
One of the implementation I see on my search results point to http://www.codeproject.com/Articles/66063/WPF-A-Nice-View-BreadCrumb-Manager#Basics. Looks good, and you should just download, provide attribution to the author, and use it.
Hope this helped. I now wait to see how many points I get for this redirection. :-;