We were customers of Talk Talk for many years as our phone services provider (we had our Broadband from Tesco). Talk Talk had a good package for us, that allowed free daytimes local calls, and cheap or free overseas calls to Europe and North America, which my wife was happy to take advantage of. We also used the Caller Id, Call Waiting and Call Divert Services (as extras).
On Friday morning in August 2010, we found that our broadband wasn't working. Also the Call Divert Service wouldn't work. After a little investigation it turned out that Talk Talk had 'slammed' us, taking over the Phone and the Broadband.
Talk Talk changed the Phone package to one without free overseas calls. Removed the Call Divert, Call Waiting and Caller Id; and disabled the Tesco Broadband and introduced their Own. Despite many calls the Talk Talk's Customer Support Lines, and after many requests to change the packages to as previous, many broken promises, we decided to leave Talk Talk completely.
So Talk Talk of course, decided to charge us a 140 Pound 'Disconnection Charge'.
So if you are thinking of joining Talk Talk, then think very carefully about dealing such an unhelpful and 'fascist' company.