Its official the next title for the Star Wars saga is The Last Jedi. Now is this movie about Luke Skywalker as the title character. Most likely . There is a couple of hints that make it most likely that Like is the last Jedi. One is that in the opening title sequences of Star Wars VII the sentence Luke Skywalker the Last Jedi appears. Also on the
Star Wars.com the mention

the next chapter in the Skywalker saga: STAR WARS: THE LAST JEDI

Also mentioned in that article is it’s written and directed by Rian Johnson and produced by Kathleen Kennedy and Ram Bergman and executive produced by J.J. Abrams, Jason McGatlin, and Tom Karnowski. And it will be released December 15 of this year (2017).
What ever maybe the case of what the title eludes to it is a huge announcement.

For more on Star Wars VIII I suggest you take a look at Wikipedias page . There is a pretty fair amount of info on the preproduction and cast.

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