It would be sweet if we could add content directly from he "Add content item" pane. Right now we have to create the content first, then reference it.
Some ideas on how to do this:
If you want this, check out http://www.wunderkraut.com/blog/an-improved-way-to-put-content-in-panels...
This could be a good addition to Panopoly, just postponing for now.
I am going to close this as won't fix since (while cool) there doesn't seem to be an easy way to get this working. http://drupal.org/project/node_pane seems reasonable, but hasn't been updated.
That being said, there isn't anything preventing you from adding your own panel content type plugin to do this!
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