Originally Posted by
Chris_W
There's not going to be a triple version of Di2 until they make an Ultegra-level version of it. I saw a comment from a journalist that had asked Shimano about the possibility of Di2 trickling down to lower groups at one of this year's bike shows and apparently the response was not very optimistic at all, so it looks like it will be at least a couple of years away for a lower-level setup (and therefore triple-ring compatibility).
Shimano has a bit of a conundrum in trickling down the Di2 technology. They can't offer an Ultegra level electric shifting group at a price point below mechanical DA7900, without killing the 7900 group in the marketplace, and they likely can't sell an Ultegra level electric group at a price much above mechanical 7900.
So it will take awhile for it come out in Ultegra, if for no better reason than market stratification.