Yes, our individual sleeping style says a lot about us, I have read somewhere although I don't have any link to substantiate this info.

Individual sleeping postures are the extensions of the individual personalities.

Only when you are awake and trying to sleep will the postures differ. After falling asleep one has no control on posture. 

After sleeping your posture is guided by your personal traits. And this is the posture that speaks of your personality.

Since there are only a few sleeping positions, we cannot expect all people to fall under these few categories, however, they show broadly a certain personality trait combined with other facts as well....

Your sleeping posture gives a hint about your personality though not a full and exact picture.

So what is the conclusion? Any relation between  personality and sleeping postures does not seem to be evolving.

Article says that there is a link. May be an indication or just a pointer.

I too feel that our sleeping position shows only a certain personality traits since there are many facets to our personality . I get links on a daily basis to our personality traits depending on our hnd shape, head shape, nose and the way we walk, sit - just about everything..

Yes. I agree with you. Every movement of your organ gives a hint about your personality