That seems to be a new expression.
I don 't understand it.
What do u mean when u say: "just saying" ?
It's not new to me. We younger people use it all the time.
Let's see, it means "take what I just said for you think it's worth." and it's usually appended onto a statement that might be construed as impolite or impolitic so as to defuse any rebuttal.
"I'm not sure if those Obama people smoke dope, but do seem to giggle a lot after lunch. I'm just saying!"
There are sometimes when I've heard a person using it as kind of a disclaimer of fact or truth, as in "This is what I've heard, I don't know if it's true or not, but think what you might think."
"He's married, but when he goes on long lunches with whatshername, he leaves his wedding ring on his mousepad. Just saying."
When we used to play "talk like a pirate" there was another phrase which would get stuck onto the end of sentences as a kind of what my mother would say meant "like it or lump it. Take it or leave it. Whatever."
It always sounded very seventeenth century.
"Arr, lads, if we'da listened to the first mate we wun't have ended up here. (pause) There it be."
Joe(There it be.)Nation