The difference to the 2010 movie (which shall be mentioned no further) is that original AVATAR creators Michael DiMartino and Bryan Konietzko are on board the live-action project as showrunners, writers and executive producers. They're absolutely 100% in charge, and have already committed to no whitewashing of the cast and keeping most of the spirit of the show intact (the promo art shows that Appa, at least, is staying the same). Apparently they and Netflix have been planning this series for "a long time" and will start shooting in early 2019.
Cautiously, intriguing and they're certainly making the right noises. If I did have one concern, it's that AVATAR: TLA was so successful because of the combination of writers and other creatives. Of the other people involved, Dave Filoni is now heading up the STAR WARS animated shows at Lucasfilm, whilst head AVATAR writer Aaron Ehasz and director Giancarlo Volpe are making THE DRAGON PRINCE for Netflix (Season 1 of which dropped last week and is great), so not all of the creative team will be available.
Still, I'm willing to give this a shot. It will be Netflix's second live-action epic fantasy series, after THE WITCHER (which will air in late 2019).