The change is immediately noticeable upon (first) log in as a pop-up details the design options update for users. I am a bit concerned with how videos appear after embedding, sometimes they disappear, but maybe that is one of the bugs will fix in the near future. I've spent time adjusting my blog layout using the new design template (see here, here, here, here, and here) and have to admit I am a bit tantalized by the claim they have "added even more themes and background images."
"Since the launch, we fixed many bugs and added even more themes and background images. But the Blogger Template Designer has only been available on Blogger in Draft, which is why we’re excited to announce that the Blogger Template Designer is now available to everyone." -- Blogger Buzz, 6/10/2010
What would it hurt to just take a look?