A simple Applescript to add the current article from Vienna (an RSS reader) to your Safari Reading List. Save to ~/Library/Scripts/Applications/Vienna.

gistfile1.applescript

tell application "Vienna"
	set the_article to current article
	set article_URL to the link of the_article
	set article_title to the title of the_article
	set article_intro to (body of the_article as text)
	tell application "Safari" to add reading list item article_URL with title article_title and preview text article_intro
end tell