Scott Berkun over at official WordPress.com blog said that "Over the last few weeks we've studied the most popular features people add to their blogs. Things like Sharing, Likes and Ratings. Previously when you turned them on it made your blog look cluttered, defeating the purpose of the features themselves. This made us sad." So, after much research, prototyping and testing, we have released "a simplified, more attractive design today as of August 11."
These features now appear as friends, lining up in orderly columns, sharing attractive styles and working together to get you the activity from your visitors you want to have.
"You may notice the designs for individual buttons have changed. One specific difference is now the 'smart button' setting is now global (renamed "Official Buttons") and not per button. If you had mixed buttons before, you'll now have them unified. This was a necessary tradeoff to make the larger design changes possible."
Here're a couple of screenshots:
Before the above changes:
After the changes: