Don't watch this movie if you have recently lost a parent/mother or wife as you will be left in tears several times throughout the movie starting nearly as soon as the movie starts. I say this speaking from personal experience as I recently lost my mother in the same time frame as the movie and each reference and song on the topic left both myself and my father in tears.
Also the actor who plays Jack the gas lamp lighter has the worst fake cockney accent and thus everytime he sings or talks it starts to get on ones nerves. Also this movie is disappointing and a lot of the things that are referenced from the original movie are lost on those who haven't seen the original movie and therefore are unable to understand what each reference means such as when Mary Poppins refers to the sayings next to the heights of herself and the 2 children in the original movie and repeats them in the new movie it leaves one confused if you haven't watched the original movie. In addition little jokes based on her previous movie fall flat without the context or having watched the original movie. This movie did and still has a lot of work needed to be anywhere as good as the original movie, but it does have some fun songs and characters and is thus not a complete failure and the kids will probably have fun watching it but might not understand some of the outdated things like gas lamps that need turning off and on manually each day and night. I could go on further, but I think what I've said should be sufficient for one to understand why this movie could have been better.