Amid all the much deserved excitement and hoopla about Children of Hurin, I wanted to give a brief nod to another book that I don't believe anyone has mentioned:
The Company they Keep: C.S. Lewis and J.R.R. Tolkien as Writers in Community by Diana Pavlac Glyer (Kent State University Press). I recently purchase it from Amazon and am about half way through. University press books can be deadly dull, but this one is enjoyable to read and has things to say I've never seen anywhere before.
Glyer challenges the standard interpretation that Lewis, Tolkien, Williams, Barfield, and others had very little influence on one another's work. (The latter is clearly the impression left by Carpenter in his biographies.) The author has pieced together diaries, letters, and unpublished manuscripts and also compared rough drafts with final products to show just how the Inklings (including JRRT) were able to challenge, correct and encourage one another. There are excerpts from unpublished materials that haven't appeared in print before. And she deals head on with comments by the authors themselves that "X" or "Y" were completely incapable of being influenced (sound familiar?
).
Some of her ideas are questionable. For example, she suggests the Lord of the Rings might have been more like the Silmarillion in structure and style if it weren't for the critique and encouragement of the Inklings. This is a stretch -- she never even considers the role of the Hobbit in this process. And she has a better handle on Lewis than Tolkien. But overall this book says some interesting things.
For an interview with Glyer by the Tolkien Library, see
here. There's also a very positive review by Verlyn Flieger that's partially quoted at Amazon.com.