It's really cool that they're going to bring this back, though I kind of wished they had set the public event to last for two weeks instead of just the one. I only managed to get a single run in, and a bunch of people I know didn't have a chance to run it at all.
Good to see. Anet seems to trying to find a solution to scheduling these hsrder/more complex boss encounters while keeping them accessible.
The outcome will likely be further iterated to introduce the Battle of LA, Breachmaker, and maybe even Tower of Nightmare. 2 which definitely seem like they are on the table for a return now that Anet has a, means to reintroduce the content.
I think bringing public back was always the plan but they needed a way to communicate it because they weren't sure how yet.