It was announced late last by Lucasfilm that Rian Johnson isn't done with Star Wars any time soon.
If anything, he's only getting started as it was announced that he is kicking off a brand-new Star Wars trilogy that'll be separate from the existing storyline and will - per the official statement - "introduce new characters from a corner of the galaxy that Star Wars lore has never before explored."
So what does that really mean in the grand scheme of things? Essentially, Rian Johnson did such a good job on The Last Jedi, they're handing him the keys to his own thing and letting him go nuts. It's understood that Johnson will write and direct the first film of this new trilogy and will then likely play a hand in selecting the directors and writers for the next three films.
As for the long-awaited live-action TV series, that's been planned for Disney's own streaming service. Details on that particular project were far more sketchy, with no official date set for its release or even a whiff of what it'll cover. Given that the Disney streaming service is set to launch in 2019, there's a good chance that the live-action TV series will feature as one of the flagship shows for it and play a major part in attracting subscribers. Whether Johnson has any part in that, however, hasn't been confirmed.
So, thoughts? Again, Lucasfilm are obviously betting big on Johnson and they don't usually do that unless they're certain of success. Considering that The Last Jedi is less than 34 days away from release, our guess is that the film is locked down and has been shown to Disney brass, who signed off enthusiastically on the whole idea once they saw it.
Given that the new trilogy has had JJ Abrams sort of on overwatch duties for the whole thing, giving Rian Johnson to spread his wings creatively and do what he wants with it should be pretty interesting.
No release date has been planned for the new trilogy.