It was a long overdue update, partially for security reasons, partially for future updates.
Do you mean that the theme changed or have you experienced other problems too?
The theme was an attempt by whoey to make the site more mobile platform friendly. We might have to revert to the old theme if we can't sort out some bugs.
If you notice anything, let us know. We already know about the layer index links on layer pages and gallery links in the right side modules.