Summary Highlighting
--------------------
`gnus-visual-mark-article-hook'
This hook is run after selecting an article. It is meant to be
used for highlighting the article in some way. It is not run if
`gnus-visual' is `nil'.
`gnus-summary-update-hook'
This hook is called when a summary line is changed. It is not run
if `gnus-visual' is `nil'.
`gnus-summary-selected-face'
This is the face (or "font" as some people call it) used to
highlight the current article in the summary buffer.
`gnus-summary-highlight'
Summary lines are highlighted according to this variable, which is
a list where the elements are of the format `(FORM . FACE)'. If
you would, for instance, like ticked articles to be italic and
high-scored articles to be bold, you could set this variable to
something like
(((eq mark gnus-ticked-mark) . italic)
((> score default) . bold))
As you may have guessed, if FORM returns a non-`nil' value, FACE
will be applied to the line.