When I first heard of Web Apps, online storage and web integration, I thought "WOW! Cool! No Installs, downloads or carrying CDs around!".
But what about security? What does Google do with my account? Does it encrypt it with my password so that nobody apart from me can use it? Does it scan through it and fill in Adsense forms? Unless I know for sure that my personal details are going to be kept private, I don't put them on the internet. So the difference is, you have control over your information when it's on your computer, which means that you have to be more weary when storing data online.
I love web apps. The idea of being able to access my files whether I'm at home or on the other side of the world is a nice idea. But, you can't fully trust something which has stored your data for free and has full access to it.
Ok, maybe I'm being a bit pessimistic here, but security does matter and unless we can have some kind of grantee that our data isn't going to be seen by the wrong people, our data is not secure and online storage may not be so good.