It seems that several shopping centers in the UK have installed a surveillance mechanism that works by monitoring the signals produced by mobile handsets and then locating the phone by triangulation – measuring the phone’s distance from three receivers.
A shopping mall could, for example, find out that 10,000 people were still in the store at 6pm, helping to make a case for longer opening hours, or that a majority of customers who visited Gap also went to Next, which could useful for marketing purposes.
While this is all good marketing and user information for shopping centers, there are a lot of people crying foul of privacy violation. But the creators of the system say that is does not access personal information, but it does log the IMEI code of the handset, which is uniqe and technically, tired to one person so linking to a person could be possible.
I guess I wouldn't mind "too much", I can just turn my phone off.