LJ has got itself a new look. You know the comments page, and in fact any page that doesn't have a theme has the default LJ layout? This is a new one. I like it... lots.
If you want to switch click this link.. if you hate it (though why you would I don't know) just visit that link again and click no. Everything will be fine ;)
You may have to refresh top get it to work.. but its purdy. I would give a more detailed anaysis, but I can't be arsed right now.