There are three possible futures with into the future.
Dystopian
Normal
Utopian
Those messages tell you that your current actions impact the way that the future neighbourhood will look. eg there will be lots of meteors with a dystopian future.
They are part of the regular gameplay and I'm not sure there is a way to turn them off, sorry, short of unchecking ITF (on the select which expansion and stuff packs you wish to play with screen with the launcher) and playing with it unselected.
Have you spoken with the time traveller that comes into your present world? I think if you don't speak with him, then those messages don't come up.
Sorry, I haven't played with ITF selected for quite some time, so I'm not really sure.