Note that you might not see this change in your personalized homepage yet.
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{ Via Blogosoped Forum. Found by Niraj Sanghvi. }
Update: It seems that Google shows the full content of a post (at least for this feed and other FeedBurner feeds like Slasdot's), but it does a poor job at handling big images and long text. For most of the other feeds, they only show a snippet. Also, you won't see snippets for ATOM feeds (e.g.: Official Google Blog or any other Blogger blog that uses the default feed).