I think it is going to work better against certain teams (like the Heat), and not against others (like the Knicks), but I love the fact that they have added it to their repertoire.
Last year Dallas used to zone a lot, and it allowed them to succeed with really just 1 inside defender, and with a lot of weird lineup combinations, often with undersized players. It also allowed them to save the legs of their aging players a bit.
I think this is exactly what the C's need. They shouldn't run it all the time, but by mixing it in, it will allow guys like KG to rest a bit from chasing guys all over the court, and allow Doc to be a little more creative in getting offensive oriented players on the court, and doing things like the 3 guard offense, etc.
The defense the C's played a couple years ago just won't work anymore. That really relied on having multiple big men who can really defend the pick and roll on the perimeter, and requires everyone to be working really hard on the switches. With no more Perk, Davis, and Sheed, older legs, and a compressed schedule, it just won't work. They can pull it off for stretches, which will be important late in big games, but it can't be the default like it used to be.
The zone is just a great weapon to have in your repertoire, and should fit this team as well as it fit the Mavs last year.