I’m working in a large organization with an Exchange account and I recently noticed that everyone within the company can see my free/busy information.I can understand this importance for a small company or a single department but to everyone else in a large company, I find that my availability is none of their business.
If you open this dialog when only the main Outlook window is open, all of these options are 'live'.
For an exchange account in Microsoft Outlook, it allows users to share their calendar free and busy information with other users.
Therefore, according to the free and busy information, other users can pick out a suitable time for meeting requires easily.
However, even though you can enable them, they won't work.
For more details, see the Microsoft article about the Impact of deploying Outlook 2007 without Word 2007 and the Microsoft Office Outlook 2007 e-mail editor white paper which has an excellent document describing why and what is not available when Word 2007 is not installed.