It seems that's definitely going ahead, and the latest rumour suggests they might already have a leading lady in mind - Emily Blunt.
Now taking on the part of Mary Poppins would be tough for any actress but we've got a lot of time for Blunt. She takes on interesting roles and is always completely committed, whether that's battling aliens alongside Tom Cruise in Edge of Tomorrow, surviving a drug war in Sicario or singing her heart out in Into the Woods - which was also directed by Marshall.
She's also British, which might help purists wrap their minds around the possibility of a new film and she's proven in the past that she can sing. At 32 (right now) she's a smidge older than Julie Andrews was when she played Mary back in 1964 - when the young lady was just 29.
We're still not completely sold on the idea of a sequel to the original film - it's an indelible classic - but P.L. Travers wrote a number of other books in the series and the idea of a companion piece with a stellar cast is starting to sound a bit more appealing.