After having just been introduced to .NET Isolated Storage, I'm ready to give it my vote of confidence. It's a pretty slick way to store info that may be required by a .NET framework application between sessions or throughout a ClickOnce update.
For me, I was struggling with an n-tier application that did not properly store connection strings in a central location. While searching for an elegant solution to that problem, this Isolated Storage bubbled up. I couldn't use it for that problem, but the next day a new problem presented itself. It was question of how to enable a (different) software application to have a 90 day demonstration license upon install. Isolated Storage gave me a way to check for previous installs (and expiration dates) between sessions and installations. You see, the store can be based on an assembly's identity, which is perfect in this case. I will tell you that anything that solves a problem for me, in an elegant fashion, is a winner in my book.