So far, the trial has been a hit. There has been a "wait" since late last night to try the beta, as Microsoft has throttled the numbers of simultaneous users that can try the preview system. At the time of writing, new users were being warned of 150 minute waits. (In our experience, the wait ticks away quickly; in one instance, 50 minutes passed by in only 10.)
Once the test environment is set up, users can explore a limited Windows desktop running Office 2007. The preview can be described as a series of tutorials meant to highlight the new features of the Office 2007 System. For example, Outlook 2007 launches with a fully loaded inbox and a window devoted to telling you what you should try out. If you're new to Office 2007, the tutorials appear to be quite informative.
More...Credit: Ars Technica