[Kushan]

Well, there's nothing extra hardware required, it has the ability to host guest networks and a bit of QoS would mean the "guest" network could have a chunk of bandwidth all to itself while the residential one still gets their full speed, whatever it may be. I believe BT's hub works the same way, except with DSL it will use up some of the potential bandwidth.

Although perhaps I am just being incredible naive about it. I'm not sure there'd be a benefit to customers other than (presumably) getting access to the Wifi networks wherever they are.