Since quite a long time people were waiting for the true sequel for the Borderlands series. The last game from the developer 2K, dubbed ‘The Pre-Sequal,’ was merely a rehash of Borderlands 2 with new locations and a Zero Gravity game mechanic.
That being said, the new Borderlands being teased is a true sequel which takes place after the Vault Hunter along with Lilith discover the presence of vaults all across the galaxy, which means, a lot of vault guardians to kill and a whole lot of loot.
Many speculations suggest that Borderlands 3 will include cross-planetary travel, a deep customization system and several returning characters like Brick and ZERO.
The Borderlands 3 will be revealed during PAX East, probably between 28-29 March 2019. Until then, you can quench for Borderlands by re-watching the awesome teaser trailer.
PS: The video is littered with Easter Eggs.