I think the folks at WattVision would concur completely. It's kind of crazy, and the idea of Smart Meters would eliminate the light sensor and wire part of the deal. I would guess that WattVision and the others in this growing market are banking on the idea that 1) the electric utilities in the US move incredibly slowly, and 2) it's not just about electricity, and even if you got a smart meter for electricity, those of us who live in cold places tend to heat with natural gas and oil -- in my house our electricity use is only 20% of our total energy use (kWh of electricity compared to kWh of gas).
In other words, this market may be like the fax machine, which was made obsolete by the Internet almost before it was introduced three decades or so ago ... yet, they're still around :-).
I still wonder why the fax machine is in such use when it offers lower reliability than the internet, I wonder if it's for security reasons. The worst you'll ever got through fax is either hatemail or someone photocopying their butt and faxing you it. However, your entire system can be taken down if you're not properly protected from receiving a single malicious email.
Now, back to the topic. I live in southern Ontario and virtually every building is heated by natural gas, and in more rural locals oil is more common, however the prices have begun matching between gas and oil where it has to be delivered. The only properties I see that are heated electrically are in apartment buildings where heat is only truly lost through far less than 1/6th of your property's surface area.
I guess my point on heat was that a thing that I think needs to be done with all of these monitors is to add other kinds of household energy uses (like nat gas, oil) to the electrical data already being captured.
Natural gas is usually delivered in units of energy called "therms", oil is delivered by the gallon (or litre), and electricity is delivered by the kWh -- all of these measures of energy can be converted into kWh so could be displayed together in a single display.
In other words, this market may be like the fax machine, which was made obsolete by the Internet almost before it was introduced three decades or so ago ... yet, they're still around :-).