Seems quite self-defeating that Canon goes all the way to merge the 1D/1Ds split into the 1DX, and now have another high resolution model, which effectively restarts the product lines.
OK, let me take that back. Maybe they actually decided to adopt the Nikon approach - D1, D1H, D1X....
Yes the 1D Mark IV and 1Ds Mark III merged for the 1DX.
They didn't say they were discontinuing 1DS models or that the 1DX was a replacement for a 1D studio body which it clearly isn't.
They didn't merge two very different camera lines.. they simply combined the best of what the 1D IV and 1Ds III had to offer.