Another of the many performance issues we hit (trust me not all of them were WPF related, it just so happens that the first two I've blogged about were)...

http://blogs.msdn.com/permanenttan/archive/2009/11/20/wpf-treeview-memory-consumption-and-performance.aspx

We hit this in the tree view you use to select which branches you want to visualize change for. A 108MB savings (on an admittedly artificially large data set), not bad :)

Brian