The BBC News site has undergone a redesign, and they have published on their blog some of the thinking behind it. The key point is that they have listened carefully to user feedback:
...we did some research asking you what you thought we should change about the site. Many of those we asked said leave it alone - don't change a thing. But it was also clear from the feedback we got that there were others who thought the site design could do with a bit of a revamp – something we’d been thinking about doing for a while.
I personally think it's a big improvement, with the content having more room to breathe. However, you can't please everyone judging by the comments on the blog...
I can't stand the new layout. The old design meant that my browser window did not have to fill the width of my screen. The new design does. I hate it.