IntelliTrace is being marketed as providing the right information at the right time. It helps you determine the exact steps required to reproduce a problem. A certain amount of information is collected by default. You can “turn up the dial” to get even more data collected.
The IntelliTrace logging only works for managed apps. It assists with viewing the prior state of an application without restarting the app. In the end this helps you diagnose problems quicker. You can also set up the tracing to perform custom actions when things go wrong. As an side you don’t need to have symbols present for IntelliTrace to work.