[quote name='Kaoz']This was my first thought, and I even typed that out. Then I googled and saw those articles (I should have read them, or at least loaded the links =P )
But yeah, this would be my bet as well.
Has the additional shoulder buttons, and those grips, yes.[/QUOTE]
The shoulder buttons are not technically additional, they're just maybe larger and moved around a bit.
Also I still see the original Classic Controller in stores today, in different packaging from what they used to be, so they're still available.
Whether or not the original will be around long after the Pro is released is a different story.