gnus-summary-default-high-score

gnus-summary-default-high-score is a variable defined in `gnus-sum.el'.
Its value is

0

Documentation:
*Default threshold for a high scored article.
An article will be highlighted as high scored if its score is greater
than this score.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 22.1 of Emacs.