[Written as a response to a LinkedIn.com question concerning the use Google and Adobe's online applications instead of Microsoft Office]
I dare suggest that the Writely and Tonic Systems applications that became Google Apps are very simple and rather slow when compared to OpenOffice.org or Microsoft Office.
The global accessibility is appealing if you are not able to use an internet file sharing service or a remote login program like LogMeIn.com but you lose a large number of important features using Google Apps and you sacrifice your personal, and more importantly, your business', privacy and security.
Finally, if you are concerned about privacy, you should know that Google's agreement reserves the right to anonymously search, index, and catalog your "private" files. This is the same thing that Google does with Gmail. While they currently only use this for targetted advertisements you should be aware that they are scanning, indexing, and cataloging all of your data.
Google exists to scan, index, and catalog the entire body of data in the world. If you like that idea, then you are contributing to it by using Google Apps.
If you want to preserve your personal and business security you should not use it.