How slim is the iPhone casing for iPhone 5?

A gossip is spreading that iPhone 5 will be 4 inches in height and slimmer than iPhone 4.
Did the new iPhone 5 casing put the rumors to an end when it compared the said iPhone 5 casing for the iPhone 4?
Also, will the earphone plug for iPhone 5 can be found at the bottom of the phone?
Is the new iPhone a lot slimmer than iPhone 4?
