Hahahaha, listening devices, maybe, and only if they are hooked into the wifi, not sure if such a thing exists or why you'd need to wifi your microwave.
This one is funny.
I can maybe understand a WiFi enabled Refrigerator... use it a "white board" for messages to family, display Outlook calendar, etc., but Wifi dishwasher? It's like they're sticking Wifi into devices simply because they can.
The problem isn't as much them being used to "listen" into activities, thought with Samsung TV's that IS a real concern, but the problem is them being used as nodes is DDoS attacks.