This belongs under 10.1 on the RFE basic list page: User Interface/Views. It's purpose is similar to the "hoist" request in that it helps keep you aware of your location on larger maps, especially when multiple neighboring but irrelevant branches are open next to the one you are working on.
The idea is for not only the current node to be highlighted but also for the trail leading from the root node to the current node to have some sort of highlighting (I would prefer edge or connector darkening). Further any open child / grandchild (and so on) nodes would be highlighted to distinguish them from neighboring nodes not associated with the current node. In other words one can easily distinguish progeny from cousins of the current node.
#1 highlight the trail from root to current node.
#2 Highlight or surround in a cloud all open nodes stemming from the current node.