Writing updates - useful or painful?

One of the things I enjoy most about reading my friend Christina's blog are her writing updates. She always has a ton of projects going at once and she has the ability to flip from one to the other depending on which muse is visiting her (or which type of chocolate she has consumed!). Reading about her progress or how she's gotten stymied by a certain chapter or character or plot point reminds me that writing is not always a naturally linear process.

Just because I have written all of my bo...