Google's rumored GDrive would allow you to access your computer files from any Internet connection, and would be tightly coupled with Google's online applications. Users should be aware of potential content ownership issues. The user agreement for such a service would likely mirror other Google terms of use, which basically gives the company complete and full access to every bit of information stored in the Google "cloud computing" environment.
The Web 2.0 trend has spawned hundreds of online data services, but taking advantage of them can quickly become a major headache, as each service strives to tether you to their online service. Each one has a userid and password which you have to set and remember, each one often installs a desktop and smartphone helper applications, and each one takes a chunk of your data (e.g. calendar, to do list, contacts, email, documents, spreadsheets, etc.) and stores it out in the "cloud" somewhere, well beyond your control.
For all the supposed problems that these applications and service avoid (mostly blaming your local hard drive), if everything is on your hard drive, it is also in your complete control and can be easily backed up. There is no free lunch here, and many of these Web 2.0 services are going to fail because there are too many services chasing customers, and when they close their doors, your data may be gone forever. Customers of the these services should make sure to keep backups of important documents, in case there are problems.