"What publishing can learn from the iPhone" points in a direction I've been thinking about for a while: we need to lessen our tie to notebooks and desktops when interacting with data.
Part of this equation is Google Gears which allows offline interaction with web applications. When I'm in the store and want to know if I have a particular book in my library, or what that wine was that I enjoyed the previous week but can't quite remember exactly which one it was, I want to have access to the information I need so I can make a well-informed decision. I want to be able to update my catalog at the point of purchase instead of trying to remember to do so later after I get home. Maybe I'm in another city, or traveling. The closer in time I can make all the tasks that go together, the more likely I am to do all of them. Managing data syncing and allowing client-side storage of data enables this.