Real life use case example please?

Klonos, I'm not a maintainer but rather someone who really wants this (or a related module) to succeed very badly.

The main use case would be a group that holds regularly scheduled meeting(s). For example, currently if you have an Event that occurs every Tuesday at 5pm, you're only recourse in Drupal is to manually create every instance of that Event. While Date API will allow you to create a sequence of events, that sequence is all stored within a single node. Anyone who has ever created,attended or hosted regular meetings understands that things change. Perhaps next Tuesday the meeting will be held at a special location or a different time. Perhaps you've created a repeating event that covers the next year and now all the information is going to change. Plus, you probably want to utilize Signup or RSVP AND have these Events display properly on a Calendar and in Views.
For these reasons and more, it is important that each Event in the sequence exists as its own node. This is what Node Repeat accomplishes. By tying into the Date API, node repeat will create a node for each date in the sequence of dates, copying all of the relevant information and tying the nodes together in a sequence.

With some final bug fixes and a couple of additional features, this could be one of the most important and sought after features in Drupal. Just look around and find all the threads where people are trying to work this scenario out, including in the Date pages.

Gregory, I've not actually been able to fully achieve the functionality. There are a couple of "gotchas" in my current implementation. You can read about it in more detail in this post on the Drupal Commons board.

As to your second question, a single node is created for every instance in the sequence of dates. So, if you create an Event that occurs every Tuesday at 5pm, it will create a node for an Event for every Tuesday at 5pm. If you were to create an anniversary, you'd tell it to create the Event once per year on a specific date. From what I can tell, the node repeat module won't function unless you put an "End Date" in. That makes sense to me since, otherwise, it would get caught in an infinite loop. You also likely don't want to clog up your database with events that are years down the road.

As mentioned in the post I reference above, you choose at the time of creation whether the nodes are published or not. That's one of my gotchas. I want them to start unpublished but be scheduled for publishing in a way that's easy on the user. Again more details in the link above.