This is notably one of the few live-action TV adaptations that's allowed to outright use Batman complete with onscreen appearances, whereas DC normally enforces an embargo to prevent audiences from being "confused" by the different continuities (apparently they don't think audiences are smart enough to know what an alternate continuity is)note this had the side effect of Green Arrow being used in his place, most notably seen in Smallville; ironically, for a while, Green Arrow himself was seen as a poor man's substitute for Batman. The fact that it's separate from the Arrowverse and is airing on DC's private streaming service may have something to do with it.
Titans marks the live-action debut of long-serving and iconic Titan Donna Troy, who had many legal issues in the past preventing her from appearing outside of comic books for the longest time (hence she only had extremely brief cameos in the 2003 animated series).
Approval of God: Marv Wolfman and George Perez have both been supportive of the series.
Many actors are of a lesser-known variety as opposed to well-known stars. The best known of the actors announced so far are probably Brenton Thwaites, Ryan Potter, Alan Ritchson, Minka Kelly, and Conor Leslie. Many other actors don't even have their Wikipedia pages yet. Australian child actress Teagan Croft as Raven is especially notable, as this is her first major role outside her homeland, only having two previous TV roles and a film back home, plus a theater role in To Kill a Mockingbird.
Once the trailer for episode 11 was released, a lot of fans predicted that many of the events would be Trigon giving Dick hallucinations.
In Japan, some fans predicted either Yuuki Kaji or anyone else from the Japanese voice cast from Attack on Titan would end working in the dub of this series due to the sole name of the show. Not only they got it right on the former, he also managed to voice Robin, the leader of the titular team.note Albeit he already voiced Robin before in Batman Ninja.
Lying Creator: Brenton Thwaites raised a lot of fans' hackles when he said that Dick split from Batman because Batman became a killer, yet nothing in the show outright confirms this and when Batman finally appears, Dick is shocked that he violates his one "no-kill" rule against both criminals and cops. Even then, this is all inside Dick's head courtesy of Trigon.
A very weird example wherein two separate actors have simultaneously been cast for the same part. Bruno Bichir was cast as Niles Caulder/The Chief for the episode that introduces his team, while Timothy Dalton is portraying him on his own show.
For many reasons, including the change of genre from animation to live-action, most foreign dubs has also changed the voice actors from previous incarnations:
The Latin American Spanish one is a very brutal one, as the dub were switched out from Venezuela (animated series) to Mexico (live-action).
The Japanese one is also pretty notorious on this, as it also replaced all the long-time voice actors from the Teen Titans's era, considering they also dubbed them in both Teen Titans Go!, Young Justice and most Japanese dubs of the DCAU. The only exception is Yuuki Kaji as Robin, as he already voiced him before in Batman Ninja, although as the Damian Wayne iteration of Robin instead of Dick Grayson.
Mostly averted by the Brazilian dub, in which, of the four protagonists, only Raven didn't have a Role Reprisal. Gar and Kory got the same voices from Teen Titans, while Dick was voiced by the voice actor of his Nightwing version in the second season of Young Justice.
Spoiled by the Cast List: A variation. Many of the characters appearing in the show (such as Arsenal, Donna Troy, Elasti-Girl, the Jason Todd Robin, Solstice and even Batman) have been spoiled by casting breakdowns that, while they've tried to be vague on who they are, were pretty obvious to anyone familiar with the comics.
Barbara Gordon was going to be part of the team when it was in development for TNT, as her pre-New 52 identity Oracle. That being said, her existence is confirmed during the Season 1 finale.
The first season was intended to be 12 episodes long, but was reduced to 11 episodes when the creative team repurposed the planned finale as Season 2's opening episode; this also lead to Season 1's finale being an outright Downer Ending until the second season resolves the Cliffhanger.