mousing over + keyboard shortcuts = multiple highlighting
If my mouse cursor is over a task row it shows as yellow. If I then decide to use the keyboard shortcuts to move the selection, the yellow highlighting caused by the mouse rollover does not disappear, resulting in two rows highlighted yellow.
Also -- if row item(s) are checked, you get lost when moving up and down with shortcut keys because checked items do not highlight.
Maybe just use the Carat symbol ala Gmail to indicate which row is selected?