I'd like the treeview to work like the combobox where you can select a node and then start typeing the text your looking for and it will automatically select that node. It would probably only make sense to search the nodes under the selected nodes parent but on a large tree this would allow you to navigate it very fast.
You are already captureing the arrow keys for navigating the tree so it seems like it would be a pretty easy extension of that to get this working.
Thanks,
Mark