My parents use ADT for home security, so why not use that infrastructure to report on their movements, their use of appliances, and the contents of their refrigerator.
I already have a proxy for this kind of home care monitoring. One of my avocations is meteorology and I provide the weather monitoring services for my town (Sherborn) and my parents town (Palos Verdes). Part of that telemetry includes the interior temperature of the building housing the equipment. Since it's network connected, I can watch my parents home to make sure it is warm in the winter and cool in the summer.
I've found this environmental monitoring to be a very helpful indicator of their well being.
I look forward to the day when home sensors offer a full report that our parents got out of bed, ate breakfast, used exercise equipment, watched television, and generally moved throughout the house in their usual pattern.
Some may consider this kind of monitoring to be an invasion of privacy, but for increasing numbers of older Americans, such tools can help them stay in their own homes longer and offer peace of mind to the family members who support them.