UPnP in home automation and the technology trend?

[eyqhuang@xxxxxxxxx]

It seems that big companies like Microsoft and Intel are promoting UPnP
technology(www.upnp.org) to standardize networking of various home
devices. However, I do not know many products supporting this standard.
Especially in this forum, I rarely see people discussing it. To me, its
TCP/UDP/IP based protocol stack looks too heavy for many home devices.
Is UPnP still a viable technology? In a bigger picture, can someone
shed some light on the technology trend of home automation area, for
technologies such as X-10, Z-Wave, ZigBee, Lonworks?

Thanks,
-EH