From the horse’s mouth
There is another way that the HomePlug technology is being taken further in the UK. Here, this device resembles a regular UK double power outlet and is installed in a regular double-gang wall bracket.
But you have a single 13-amp UK power outlet plus a 4-port 10/100 managed Ethernet switch. It then connects to a HomePlug AV 200Mbps powerline network segment that rides on the existing ring-main wiring. Business users who value functionality like VLANs can benefit from the Ethernet switch being a managed type.
The Website pitched this unit as being a network on-ramp or off-ramp for a HomePlug AV segment and cited applications like historic buildings where modifications to power outlet locations may be against the heritage-protection rules for these buildings.
Personally, I would recommend this kind of outlet to be compliant to HomePlug AV2 and would be best suited to projects where you are reorganising power outlets in a room or building. In the home, it would be more applicable for locations where a cluster of computing or audio-video equipment would exist. I would also value it as being useful for caravans or temporary buildings or, for that matter, any outbuilding application.
Similarly, the “Power Ethernet” unit could be made available with an integrated 802.11n Wi-Fi access point for “infill use” in covering wireless-network black spots but it is easy to think of this device as being something that can provide HomePlug in a semi-permanent manner.