Anyway, as soon as the rep answered the call she already had my business account details up - which means she could see my Caller ID. If YP was still Telecom owned I can see how this may have been seen as OK, seeing as Telecom do state that your number is still visible if calling emergency services or a Telecom Call Centre.
However, Yellow Pages was sold and Telecom no longer own the company. It concerns me greatly that their call centre can see my Caller ID. How many other places can?