-A real cinnamon stick is a light brown color not a dark color
-The aroma of a real cinnamon stick will be light whereas the Cassia version will have a strong aroma
-Ceylon (good) cinnamon looks like a cigar whereas Cassia looks like an empty tube
-Taste test: Ceylon has a sweet taste whereas Cassia has a flat taste
-Saigon Cinnamon is bad (Cassia) whereas Ceylon Cinnamon or Real Cinnamon is a winner
So great information but where can I buy the real deal? The truth about it, is that Real Cinnamon has not been present in America for at least 100 years. There are health food stores that carry the real deal and I found this website http://ceyloncinnamonproducts.com/Statement_Quality.php that has the real deal as well.
Just be aware of what you are putting in your body. Remember that stores and food suppliers must market there foods so ignore the flashy marketing terms and read the fine print!