Yes, the higher the number, the larger the image appears on the sensor. 1:1 means that it is the same size on the sensor as it exists.
That being said, the difference between 0.6x and 0.72x is about 20% - meaning what fills the whole frame on the 12-50 will fill 80% of the frame on the 12-40. Not exactly a dramatic difference.
Looks like the 12-40 will replace my 12-50 and maybe even the 14/2.5. pancakes are handy though. 20/1.7 that one is not as easy a decision.