I was successful to overlay the exchange calendar into SharePoint calendar. But is there an option on what I can display in SharePoint site, for instance I want to display title and body of an appointment in the SharePoint calendar. Also can I make changes on exchange events from SharePoint site?
y default, the calendar will only show limited (free/busy) information about the event for the logged on user. This setting is controlled by the permission level in the outlook calendar. You can change this from "Outlook | File | Options | Calendar | Free/Busy options" under "Calendar Options". The permission level is set to "free/busy time" by default. If you wish to show more details in the Exchange calendar in SharePoint, you can change the permission level to "Full Details".
Check the Step 4 in this blog for permission issue.
For second part, i dont thing you can update the Exchange calerndar from SharePoint, i never tried it.
Their is 3rd party web part available for this Virto Sharepoint Calendar - Exchange Edition