For the high bandwidth stuff, AV, the good things are locked up by the software content providers. You pay top dollars for media server but the quality is 2nd best at best. Otherwise, all AV units should be Ethernet (most likely wi-fi) appliances. How simple. With under $40 for a full wifi router available at hardware stores, there's not much price difference adding wi-fi capability to most audio (7.1 sound) and video (plasma) equipments.
With the low price example of wifi webcams, and wifi surround speakers, the only reason the other AV are not wifi is because the providers don't want to. Either you have to pay up for say multiple satellite boxes in multiple rooms, or you redigitalize the analog signal. But if I have that sort of large house, and spend that sort of money of AV home automation, I would 1st find a house in those experimental 100M or200M cable areas. (1M for DSL/cable, 5-10M for high speed cable).
It's not going to happen for your toaster to become an internet appliance, for a long long time. So a low bandwidth home network is required. But the major companies aren't interested in low tech stuff that help save your trouble and money. They are looking for a Trojan horse into your home, so that one day everything with an electrical cord has a XXX home network adapter.
Zeebee, an open standard, looks exactly like one. Spread spectrum at2.4 GHz to co-exist with wifi. It's a full mesh network like, allowing multiple controllers at the same time. Interestingly, spread spectrum isn't associated with power saving for battery operation. You always have longer battery life with narrow band modulation. And any sensible designer will think about a power supply inside a wall switch, perhaps charging a backup battery, rather than requiring all the batteries be changed every year or so.
Zwave is another full sort of network. It's say open, but I doubt if the standard belongs to the public domain. Battery in responders should have longer life if only batteries can be used. But narrowband signals should have more propagation problems inside homes. If you have few devices to control, scattered in a farm, I doubt if the technology is any better than simpler systems. And if you have lots of things, I think at some point you need to find a network troubleshooter instead of an electrician.
Insteon is promoted as a dual carrier, power line and RF, network. But in reality, it's x10 in disguise, it's compatible too. Forget about the claim that every device repeats power line signal and RF signal as in a mesh network. Most switch will be dumb, listening (and repeating) for power line signal only. The RF devices is sort of like the X10 transceivers. It's not a network - you can't have two controllers in two room controlling the media center without affecting each other. One command is propagated to the whole house and repeated several times. No big network or chip players will be interested.
Again it's open but I think not in the public domain. That's no big deal as long as the switch is cheap at $20 with a dimmer, compared to $10 for x10 without a dimmer. I'm not going to pay $40 each yet.
The characteristic simulcast feature - either you think it's brilliant or it's laughable. Well the company white paper sounds like a 1st year engineering student just completed a project. On the RF side, you may imagine a mesh of reliable RF repeaters. In reality, you should install only two provided in the starter kid, to solve the phase coupling problem, and no more. Simulcast is self inflicted multi path propagation interference. FSK modulation is OK, less likely to reduce the signal or cancel itself altogether, but any significant numbers of RF devices simulcasting and repeating is mind boggling. Insteon's idea is for you to install the two, move them around if necessary to get good reception, and don't move them afterward. So if you buy the coupler repeaters for X10, it's just as good.
Now back to the power line, simulcast using BPSK is a joke. If you win the luck of draw in the beginning, adding or removing a switch will risk killing off the Insteon signal to some appliances or part of the house. Unaware users will experience some very subtle problems that is hard to solve. Getting a signal meter is a must.
So the few advantage of Insteon over x10 is the acknowledge signal. So if you turn off the lawn sprinkler because it just rained, the sprinkler should really be turned off. Ideally, the remote controller should have an indicator light for the on/off status polled from the device, and a toggle switch. But the controllers I seen are x10 like, one on and one off switch. So the dumpiest way to do it is to repeat the command 3 times if no acknowledgment is received, and then silently give up. It make little difference to x10. If your dryer noise disrupts the signal to the sprinkler, it's likely to kill the repeats too.
Insteon suffers from the same power line problems. All appliances change the impedence to the signal, and bad DC adapters are very good signal attenuators. Two laptop chargers will have easily noticeable unreliability effects, if not killing the signal altogether. You can plug in one Insteon RF repeater, but you can do it more elegantly with a cheaper filter (isolator).
Noisy appliances are best dealt with by maintaining strong signals. Outside effects, like power surge, spikes that drive the electronic crazy, are supposed to be rare, and that should not happen with a good power supply circuit within the wall switch. Brownout effects are just like the manual override feature of dust to dawn outdoor lanterns, that should be an option.
So unless you have a lot of money, a $50 switch controlling $1000 lighting, or you need to control something that you cannot see, and it have to be reliable, then x10 is not too bad.