Details are sparse at the moment, but more should come out of E3.
From the press release:
We've been hard at work at Telltale creating an all-new iteration of the iconic Batman story that puts players in the suit of billionaire Bruce Wayne, just as much as it will put them behind the mask, deciding how to carefully navigate a complex drama, rich with action, crime, corruption, and villainy lurking around every corner of Gotham City. The complex life and fractured psyche of Bruce Wayne has lent itself to becoming a bold evolution of the signature 'Telltale' role-playing experience, and we couldn't be more excited as we prepare to debut the series to players across the world this summer.
Rendered to look like a living, breathing comic book, Telltale's vision of Batman will feature an award-winning cast of talent, including Troy Baker in the role of Bruce Wayne, Travis Willingham as Harvey Dent, Erin Yvette as Vicki Vale, Enn Reitel as Alfred Pennyworth, Murphy Guyer as Lieutenant James Gordon, Richard McGonagle as Carmine Falcone, and Laura Bailey as Selina Kyle. We'll be able to reveal additional cast and characters as the season progresses.
More info and images: https://www.telltalegames.com/blog/106859/batman-the-telltale-series-unveiled-in-first-look-ahead-of-summer-2016-premiere