Whilst it has been slow to take off in Europe and the rest of the World, GoogleApps for Business have been as huge success in the US. In Mid 2007 we electronically surveyed 550k US companies to see who was using GoogleApps mail services and it hardly hit the Radar.
Re-running the Survey in Mid 2008 the results couldn't have been more different. GoogleApps had arrived, and the demographic is right in the heart of the US business, companies with between 20-250 employees.
You're probably all Google Chrome'd out by now but a significant part of the Chrome announcement is that it has an application development kit called Gears that allows Web App Developers; like ourselves, Salesforce, etal, to build Off-line features into our products, making them portable.
For Google, this means that users of GoogleApps for Business will soon be able to compose a Gmail that includes a GoogleApps Spreadsheet sitting on a plane, and have it sync up and send as soon as they are connected to the Internet again.