RSS Feed with Headlines Only

“Is there a bloginfo key that allows me to create an RSS feed which only publishes the Headlines?“

No. To do something like this you’d need to modify one or more of the feed scripts to output your feed without post content. One way to do this is to use a GET query (let’s call it “headlines”), then have the script display post content *only* if the query is not passed to it. So if you use:

http://my.site/feed/?headlines

to only call up headlines in your feed, then in wp-rss2.php (for RSS2 or the default feed), add this just after the <guid> line:

<?php if (!isset($_GET['headlines'])) : ?>

and insert:

<?php endif; ?>

before the closing </item> tag.