No, so far. Scenarios doesn't really add anything new for people that have played the game for a long time with challenges. And as far as I have seen once you start a scenario it's the same game as before...
It doesn't feel like there was much development going into it either. Right now it just looks like a larger aspiration goal in the upper left. Will there be sub goals? Will the game encourage you to do different things?
I think more development time should have been spent giving us the player the options to create our own scenarios and set sub goals, set rules that have to be followed when playing, rules like "you can't have a job" etc.
What makes challenges fun to watch when other people are playing are also often because the person that's playing is making it interesting, the challenges themselves are very basic, like the 100 baby challenge, you have to make it interesting by changing things around, scenarios doesn't change that as far as I can see.