Will the Show's Original Cast & Crew Return?
Notably missing from the announcement are the names of any actors, writers or showrunners. But, again, this news just broke so while presumably talks have taken or are taking place for cast members like Rob Paulsen (Yakko) or Tress MacNielle (Dot) and writers like Paul Rugg and original showrunner Tom Reugger (who worked together on the recently concluded Disney series The 7D) to return, it's possible a search is underway for replacements for at least some original series regulars.
The most notable example of a revived show moving forward without the original cast or crew is the current iteration of The Powerpuff Girls. When the new Powerpuff Girlsdebuted last year, it did so without the involvement of original creator Craig McCracken (who was working on his Disney show Wander Over Yonder at the time), any of the original writers or producers and, most controversially, without most of the original voice cast. At the time, Tara Strong, the original Bubbles, compared the recasting as "being stabbed in the heart."
But there's an added wrinkle here. For quite a while now, the Warner siblings themselves -- Paulsen, McNielle and Jess Harnell (Wakko) -- along with original Animaniacs composer Randy Rogel have been touring America performing songs from the original show under the name Animaniacs Live! to sold-out venues and wide acclaim. With their original performances still heavily in people's minds, Hulu and Warner Bros. has to be aware on some level of the backlash they would face should they go the recasting route.
Luckily, we probably don't have to worry. Actor Maurice LaMarche followed up on the news of the series' return with a Tweet where he reprised his role as Orson Welles in order to read the announcement to fans. This, after an earlier tweet in which he stated, "I guess I can talk about this now."
What Will the New Animaniacs Look Like?
The overriding mandate of Spielberg's production work with WB Animation in the '90s was to recapture the zany gags and equally madcap visuals of the Golden Age of Animation. In Animaniacs' case, that meant paying top dollar for production studios like Tokyo Movie Shinsha (now TMS, who also worked on Batman: The Animated Series) and AKOM to turn in a show that had a higher cel count (that is, more hand-drawn frames of animation per second) than its contemporaries.
But except for the Don Hertzfeldts or Bill Plymptons of the world, who mostly draw every frame themselves, hand-drawn cel animation is largely a thing of the past. Shows like The Simpsons or Bob's Burgers are drawn by animators working digitally both in America (where the writing and storyboard phases of animated shows often happen) and overseas (where the final, most labor-intensive parts of the animation process take place). Thus, it's not hard to imagine a version of Animaniacs crafted in the vein of Disney XD's current revival of DuckTales or My Little Pony: Friendship Is Magic , the latter of which is animated in Flash. Could such a style stay true to the original Animaniacs' Tex Avery-homaging mandate?
It's possible but, until the first promo artwork and video from the reboot is released, there's really no way to know for sure.