There are actually 4 "original" formulas:

The original comes in the glass bottle.
The plastic bottle is usually more carbonated.
The can has more sugar in it (to over come the metallic taste)
and foutain Coke has a variable mixture to it, allowing the store dispensing it to vary the level of syrup to carbonation.

And Pepsi...
well that stuff just gives me gas

 

Did you check the nutritional facts on the back?

 

 Nope. I quit that along with listening to the words of songs (DAM YOU Susan Vega with your catchy "My Name is Luka" - Dam YOU!)