There's no new footage in the teaser, but it's now confirmed that the final season will arrive in April 2019. HBO has been annoyingly evasive about giving an answer as to when the final season will arrive, and even now, they're still evasive.
April 2019? What is that? Is that the beginning of the month? The end of the month? WHY ARE YOU LIKE THIS, HBO? JESUS, WHAT DO YOU NEED?
Anyway, here's the teaser. Get hype, people. GET HYPE.