I use Instant Messaging services for night time leisure to pass the time to go to sleep and or to occupy myself if I am unable to sleep.
I use the cellphone to only call when I want to see how someone is doing but 9 times out of 10 I am using it because someone called me.
I only text when I need to know something but do not want to be dragged into a conversation with that person.
So I use all three, perhaps IM for 2-3 hours a day, cell phone for 1-2 hours a day, and text like once a week.