rocknbil - 4:37 pm on Apr 19, 2012 (gmt 0)

What if the Javascript (jQuery) doesn't execute? Many S.E.'s don't parse Javascript. So if it "looks like it works" it's only because you have JS enabled.

The only solid solution is the one suggested above - grab the feed content, use preg_replace to add nofollow to the link, then output the modified content.