I suspect it's something like "Power Line Communications" AKA "Broadband over Power Lines" - this will mean the death of SWL'ing as we know it, as it tends to be out in the country as opposed to in the towns and cities where broadband is already well established on copper cables.
Fortunately we are supposedly going to fibre soon, but I won't hold my breath waiting. My broadband is going quite well with 12Mbits down and 800kbits up at the moment - before the neighbourhood kids come home from school anyway!