I think having access to my power consumption at any point in time would provide a new level of visibility... and an aggregate view would do more to enlighten people about their individual resource utilization. If you can monitor it you can control it... data on a monthly basis isn't enough in my opinion.
Why would I want to monitor usage on a single plug? If I could have the same thing monitor my entire house and update twitter, email, widget, mobile phone app, etc. it would be very compelling. Having a view in the aggregate would encourage people to disconnect devices using power in stand-by mode, etc. And power usage tracking would become a competition between peers. Google to the rescue? http://www.cringely.com/2009/02/power-to-the-people/
True... but does the perpetrator sound like someone with that sort of competency? No. If he did he'd probably have the sense to see if the machine was phoning home. I doubt he hacked into this guys account so he could download porn all day.