When doing an incremental find, the previous search should remain. Currently when you click out of the find search box and then use the hot-key to go back to it, the contents of the box are removed.
Instead the contents should be highlighted (so when you begin typing it removes the old), but also allow for continued incremental searching on the previous search term.
This behavior would be more in-line with what Emacs and Textmate do.
Perhaps it could be an user-configurable option if making it default doesn't make sense.