(Email from Vincent Manis)
The Introduction (p. 2) appears essentially unchanged since R4RS (and maybe earlier), and should really be updated.
In `Background': the first couple of paragraphs are essentially ancient history now, and might be compressed somewhat. A new paragraph should describe what has happened to Scheme since R4RS. Mention should be made of: IEEE Scheme, R5RS, R6RS. It has been used at many more universities and schools. Many books have been written about Scheme. It has been used for building applications running on everything from mobile devices up. It has been used as an extension language for many applications. Many other languages have adapted features from it, with greater or lesser success.
The Acknowledgements' are again ancient history. I very much doubt that the authors of R7RS are actually thanking Betty Dexter, though they might still be thanking Don Knuth! :) I suggest prefixing the current Acknowledgements with the sentence Earlier versions of this Report included the following acknowledgements.' and then adding a paragraph at the end saying `The authors of R7RS wish to thank the following parties...'
In `Additional Material' (p. 61). The Internet Scheme Repository has fallen into desuetude. Perhaps mention can also be made of readscheme.org.