Point of presence TV still seems to be a graveyard with more and more high profile failures and problems. Even the super successful Tesco have struggled with their Tesco TV service (incidentally, despite shopping regularly at three of their largest stores, I've never seen Tesco TV in operation). Other attempts at point of information in places from elevators to gas station forecourts have equally failed.
Narrowstep ran a test a couple of years ago running High TV in a bar in central London. The ad slots delivered largely beer ads and the bar claimed that sale of the beers advertised on the channel increased four fold when the system was installed.
So, why is this such as graveyard ? Well, the cost of rollout was relatively high until IP delivery cam along, but the main culprit seems to be an inability to sell advertising.
It'll be interesting to see how the next generation of point of presence TV services fare.