The third volume of C.S. Lewis' Letters, edited by Walter Hooper, was released a few months ago by HarperSanFrancisco. A writer named Michael Ward has reviewed the book for Books and Culture. An interesting review, which can be found here.
In some ways, the review is as much about Walter Hooper as it is about C.S. Lewis, but that's part of what makes it interesting. Hooper has always been a somewhat mysterious figure -- he was briefly Lewis' personal secretary; he's edited and prepared for publication a lot of Lewis' posthumous work; and the late Kathryn Lindskoog, another Lewis scholar, accused him of playing around a bit too freely with Lewis' legacy. The lynchpin in that argument was that Lewis hadn't really written the story The Dark Tower, which Hooper claimed to have found among Lewis' papers (and subsequently published). Although I'm sure her arguments were more sophisticated than this, what Lindskoog's main argument seemed to be was that the story just wasn't good enough to have been written by Lewis.
That last accusation seems to have finally and thankfully been laid to rest, and Ward has only good things to say about Hooper's charitable stance towards Lindskoog in the footnotes of this particular volume, although obviously Hooper had a big chance to say "I told you so." It turns out that another scholar had seen the unfinished story among Lewis' papers. And that even C.S. Lewis (thank you very much) could write pretty awful first drafts.
The review is also worth reading for the insights into the collecting and editing process behind such an enormous project. There are approximately 2,000 letters in this final volume! And many of them had to be unpacked (literary references/allusions, explanations as to who Lewis was writing to and why...Hooper even tracked down some of the correspondents or their descendants so he could try to get a handle on the "unheard" side of various conversations). Sounds like an enormous task, but also enormously satisfying.
I've only read Lewis' Letters to Children (a slim little volume edited by Marjorie Lamp Mead) but I am thinking I really need to put Hooper's three volumes on my to-be-read list. I love reading letters, and I love Lewis.