"This new design centers around photos that are interesting to you. We wanted to give you faster access to the newest photos from your family and friends along with some great photos from the talented Picasa community. When you log in to Picasa Web Albums, you will not only see your own albums, but albums that have been shared with you, the latest public albums from people you follow, and featured photos from the Picasa community right on your home page," explains Google's Ping Chen.
While "recent activity" has always been a section on the homepage, now you can no ignore it. YouTube's homepage has recently switched to a feed view, a stream of activities popularized by Facebook.
If you don't like the new homepage, bookmark this URL: https://picasaweb.google.com/lh/myphotos or click "My Photos" when visiting the homepage.