I just wrote about this (http://www.dailyblogtips.com/nofollow-feedburner-feed-links/) and would like some second opinion. In summary my argument is the following: sometimes the Feedburner feed page will rank higher than the blog itself, which is not optimal since readers might end up visiting only the feed page (they will not see the design, the comments, the ads, etc). Secondly Feedburner feed page also is an exact duplicate page of your homepage (provided you publish full feeds). If you include a nofollow tag on the links for feedurner you should reduce the duplicate content penalties (since you are no longer supporting that page as far as Google can tell) and you will also make sure that your blog ranks higher than the feed page. Any thoughts?
I saw this the first couple days the site in my sig was up, until it started getting a few organic links. FeedBurner actually linked to my site from one of their PR8 pages (I think it was called FeedBurner Buzz), so I wasn't going to jeopardize anything by putting in nofollow's.