http://www.archives.gov/exhibits/charters/charters_downloads.html
...the comma is in fact where others have claimed it's located on the original parchment.
See for yourself.
Hint: open the Constitution image that's the third one down, out of four images placed vertically, in the second section from the top of the page. Use the magnification function in the browser viewer. FYI: I'm using MS Vista.
Isn't the FReeper community grand? ;o)
Well, wouldn't those old guys have a hoot if they could see us today poring over their words--and commas--on computer screens!