No plot line has been revealed as of now. Lucas has his notes for what he intended to do, but has never confirmed anything.
JJ Abrams has only just been announced as the next director and neither he, Lucas, Lucasfilm/Disney or any of the producers have given any indication of what story they may or may not use, or if it will be an entirely new creation.
The non-G-Canon "Expanded Universe" books deal with the years after the Battle of Yavin, but again - there has been no indication that any of these stories will be used in any way.
As of now, the next chronological book would be The Truce At Bakura, which Wikipedia summarizes as
While recovering from their victory against the Empire at Endor, the Rebel Alliance intercepts an Imperial probe containing a distress call for the Emperor. The message details a lizardlike race of aliens invading the Outer Rim planet Bakura. With Palpatine dead and the Imperial Navy scattered, Luke Skywalker volunteers to lead a force to intercept the alien invasion and save Bakura.
It is, however, a single novel.
The next major story arc (i.e., trilogy), would be The Heir To The Empire storyline. Wikipedia summarizes it as
Heir to the Empire is part of the Star Wars Expanded Universe, and takes place five years after the events of Return of the Jedi. The Rebel Alliance has destroyed the Death Star, defeated Darth Vader and Emperor Palpatine, and driven out the remnants of the old Imperial Starfleet to a distant corner of the galaxy. Princess Leia and Han Solo are married and expecting twins. Luke Skywalker has become the first in a long-awaited new line of Jedi Knights.
Thousands of light years away, Grand Admiral Thrawn, the last of the Emperor's Warlords, has taken command of the shattered Imperial Fleet, readied it for war, and pointed it at the fragile heart of the New Republic. Thrawn is searching for a Dark Jedi and is succeeding in restoring the Empire.
Officially, neither they, or any other existing story are more likely to be used as the source story for the new movie(s).
It should also be noted that the site run by SuperShadow is a very old, very fake site. It pre-dates the prequels and all of his supposed inside-scoops were confirmed to be complete fabrications.