Refrigerators, stoves, and washing machines are also heavy as hell. Like our plasma TVs, once situated their weights are irrelevant.
Refrigerators, stoves, and washing machines are rarely suspended from walls or situated on consoles from which they could easily be tipped over; televisions, OTOH...
The weight of something that is typically mounted to a wall seems very relevant. Most TV mounts are not rated to hold the weight of a plasma TV. A poorly installed or insufficient mount could definitely fail.
Plasma TVs not mounted to the wall are also concerning for safety reasons. A plasma TV tipped onto a young child would likely cause significant injury above and beyond what an LCD would cause.
I loved my plasma but I feel like the weight was a real issue.