Different Stuff for your places?

So if you are in multiple places -- let's say Facebook, Google+, and Twitter -- like I am, should you put different entries in each place? I go from one place to another and find much the same things in each. Twitter is a bit different than the other two, primarily because of its 140 character limit. That tends to make it the announcement place pointing to other places like this, where you can be more verbose. But, because of automated posting programs, I'm finding the same thing in both Google+ and Facebook. Makes keeping both sort of silly. Sure, Google+ has circles while Facebook has friends, but the content seems to be pretty much the same. Should it be? Are they like competing retailers who carry the same stuff and only differentiate themselves by price or service? Both are platforms and I wonder if they could differentiate themselves by the content that can be applied to either.