It looks as if a tennis match of sorts is starting between Google and Microsoft. Microsoft's new OfficeLive product (http://officelive.microsoft.com/), set to be released soon, was seen as a response to Google's online document, spreadsheet, and presentation tools. From the looks of things the OfficeLive would be much nicer, as it would allow you to work with your files in their true format as office documents. According to this article (Google Plans Service to Store Users' Data) in the Wall Street Journal, Google now plans to offer a storage space for users' files.
One thing that will hopefully result from these new tools is that teacher collaboration will increase in quantity and quality. It will be up to the teachers to make it happen, but it seems a logical and easy way to collaborate on lesson plans.