I suspect that MTH has a pretty good handle on what sells and what will sell in the future. They probably figure that they will not sell enough of the DCS handheld's to make it worth their while vs. the Wifi ap.
It might also be that it cannot be updated without a major overhaul to do what they want it to do (or what we will want it to do) in the next few years. The Smart Device/Wifi Ap probably has far fewer limitations in terms of features and innovations over time.
That being said, I still like to use the handheld and probably use it about 50% of the time.
