I was wondering if it is possible to show all the members of a team calendar on a SharePoint calendar? I know you have the calendar overlay option. I imagine when adding the calendar it would have to be approved by the user?
The Exchange calendars that are referenced are typically the shared public folder calendars which have a set address. It looks like you can also reference the current user's calendar, but I've not seen an option to identify a team member's calendar. It is also important to note that there is no approval process for a stated calendar, users would need to have access to view the entries.
Typically the way that I have handled a team calendar like this is to make the SharePoint Calendar support inbound email and have user's include that address when sending group meetings so that it can be displayed in the SharePoint as well as the local Outlook calendar.
If you are looking to see team member schedules on SharePoint 2010, you can use the Group Calendar feature.
If you would like to add the actual appointments to a SharePoint calendar, this is not possible out of the box. We have been working on an Outlook add-in called ProperSync, which can connect an Outlook calendar to a SharePoint calendar. You can find more information at www.propersync.com.
*Disclaimer - I am part of the ProperSync team and hope this is a relevant and useful posting.