Here's your weekly update on the progress Rafael and I are making on "Windows 8.1 Book," our new book about Microsoft's latest operating system.

As you may recall, Windows 8.1 Book is available now while we're writing it for just $2, or you can set your own price. Versions for Kindle and Nook are on the way as well.

Here are the updates we made this week.

Music 0.5 and Book 0.13

Here's a quick and dirty update to the Music chapter that includes two new sections on importing playlists (curiously left incomplete previously) and creating playlists from the web.

Windows 8.1 Book + Windows 8.1

I think I found a great solution for reading Windows 8.1 Book on Windows 8.1, which, when you think about it, is probably how many people will want to read it. Today's update of the NOOK app for Windows 8.1 adds a number of new features, among them the ability to sign in with your Microsoft account. And because this app can read on-device ePub files, you can use it to read a good-looking version of the book.

We'll have more soon—I'll be writing today, for example—but the book is currently about 163 pages long, of a projected 400 to 600 pages when completed.