Menu items in applications (Such as File/Edit) and on the Menu panel (such
as Applications/Actions) should highlight in the same way that toolbar
icons do on mouseover.  The reason for this is that new computer users are
not going to realize that those items are clickable.  By providing a
highlighted area around the text, we'll be providing feedback to let people
know that this is an area that can be clicked.  It also would let people
know which menu item they are currently hovering over.  Currently, the menu
items highlight when you are in a menu structure (such as File or Edit) so
it should be a easy fix.  

Both Mozilla and Windows appear to follow this behavior, so I think there
is a pretty good precident for it (and pretty good reasons as well).

Thanks,
Mark