On the v5, it takes just as long (quicker when you consider the fact that when mating you get the eggs straight away) to get to the next generation on v4 and v4.5.
Baby to Child: 1 hour
Child to Teenager: 48 hours
Teenager to Adult: 48 hours
Being able to use dating channel: 48 hours
Here is some other information for other versions.
v1-v3:
Baby to Child: 1 hour
Child to Teenager: 24 hours
Teenager to Adult: 72 hours
Being able to get matchmaker visits: 72 hours
v4-v4.5:
Baby to Child: 1 hour
Child to Teenager: 24 hours
Teenager to Adult: 48 hours
Being able to get matchmaker visits: 72 hours