This might give you a clue.
When I look at http://51bits.com/feed/ in Chrome I see
51bits » Page not found http://51bits.com UI Design & Development from Sydney Sun, 16 Jan 2011 00:10:52 +0000 en hourly 1
That seems like part of the page content is displaying where the URL it couldn't find should be displaying.
When I go to http://51bits.com in IE7 the main site tells me
coming soon for IE.
When I go to http://51bits.com/feed in IE7 I see
<?xml version="1.0" encoding="UTF-8" ?>
- <rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:sy="http://purl.org/rss/1.0/modules/syndication/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/">
- <channel>
<title>51bits » Page not found</title>
<atom:link href="http://51bits.com/feed" rel="self" type="application/rss+xml" />
<link>http://51bits.com</link>
<description>UI Design & Development from Sydney</description>
<lastBuildDate>Sun, 16 Jan 2011 00:10:52 +0000</lastBuildDate>
<language>en</language>
<sy:updatePeriod>hourly</sy:updatePeriod>
<sy:updateFrequency>1</sy:updateFrequency>
</channel>
</rss>
No posts, because no content is displaying. None the less I am seeing the feed header.
I wonder if something you are doing is inadvertently redirecting the feed URL. Why would it work in IE7 and not in Chrome? You have no site on IE7 and the feed header works, and you have a full site in Chrome and can't access the feed. Why?