..... My setup right now is almost purely X10. I may look into some insteon, UPB, and/or z-wave in the near future if the X10 market slows enough.
I would never restrict my Home Automation (or my diet) to just one flavor. Although I mostly use X10... I use non-X10 and plenty of "non-X10 controlled" automation. There are no rules on what a good or proper setup consists of.
I've was never able to get a crystal ball to work for me. So... I really have no idea what the future will bring. But if you think GE is a well managed and cleverly positioned politically than Z-Wave should look pretty good to you. If you want to hang on to the coattails of the big boys like the alarm and cable company's....
aren't they invested in INSTEON(?).
The smart money would be on hangin loose and just waiting to see how things play out. But HA Systems aren't static... most people are constantly changing and improving their HA. Where do we go from here? And that is the question for most of here...
I think. What do we do... whats next. Its a good time to own spare parts. Most stuff seems somewhat backwards compatible to the X10 protocol.
Remember..... we're all in this together.