As a blogger, how do feel about blogs that display summarized versions of your posts using your rss feed? Do you think this will help increase your traffic, because it gives you another venue to publicize your post, which makes it a good thing? OR Do you think that people will be satisfied with just the summary and never bother to click-though to your blog, which makes it a bad thing? Note that if your feed is used to create summarized entries on another blog, then the post titles may be identical, thus creating another page with the same page title on search engines.
I've always preferred summary instead full content feeds. Basically for 2 reasons: 1. the feed was born to be light and not a full list of articles 2. if the user is interested in open the browser and read the article, if not he safe time. A short description gives a quick idea about the content.