Snyder, who is currently putting the finishing touches to this year's Superman reboot Man of Steel alongside producer Christopher Nolan (The Dark Knight Rises), is said to be working on "an as-yet-untitled Jedi epic" loosely based on Kursawa's 1954 samurai classic, "with the ronin and katana being replaced by the Force-wielding knights and their iconic lightsabers." According to Vulture's insider, it's likely that Snyder's Star Wars "will not be considered part of the “numbered” episodes, but rather a stand-alone film set sometime post–Episode VIevents."
According to Disney CEO Bob Iger, the company plans to release a new Star Wars movie every two to three years, with Star Wars: Episode VII arriving in 2015, followed by Episode VIII in 2017 and Episode IX in 2019. So, assuming Vulture's report is accurate, Snyder's either going to have almost a decade of prep on his Star Wars movie, oraudiences are going to have to get their heads around several Star Wars stories running at once ["Daddy, where's Junior Skywalker and Bar-Bar Binks?"].
Unless of course this arrives pre-Episode VII...
Update - Well, that didn't take long... A spokesperson for Zack Snyder has moved to deny the story on the director's behalf, telling The Hollywood Reporter: "While he is super flattered because he is a huge fan, Zack is not involved in any way with the new Star Wars. He is currently in post on his two films, Man of Steel and 300: Battle of Artemisia."