The Sandbox was mentioned in Microformats: Empowering Your Markup for Web 2.0, by John Allsopp (note John’s blog is using a Sandbox-based theme running WordPress).
You can download the table of contents, appendices, and a sample chapter or two before you purchase the book. It’s quite funny, actually. I went looking for more information on Microformats and found this book. I downloaded the appendices and imagine my surprise when I see the Sandbox theme there.
Of course I bought the book. And it’s help me get my head around what Microformats are and what they can do.
