It was probably good for some while it lasted, but BT Vision subscribers who have been able to view catch-up TV content for free via the IPTV service component of the BT Vision video on demand/Freeview hybrid service are now going to have to pay a monthly subscription fee.
BT Vision now has a TV Replay Pack that costs £3 per month and covers the 4oD and BBC iPlayer service. Technical issues are cited on DigitalSpy as for the reason why BT has made this move. We presume this is because viewing this material required a Quality of Service (QoS) session to be booked and paid for by BT Retail and as usage increased they were unwilling to subsidise this from the income that BT Vision normally generates.
BT Total customers are of course still able to view 4oD and BBC iPlayer material for free via other computing devices using their broadband connection. The lowest priced Option 1 product with its 5GB allowance will probably let you view 15-20 hours of BBC iPlayer streams over the course of a month dependant on what else you use your broadband connection for.
The BT Total usage allowances recently changed from being just download allowances to be a combined total for both upload and download usage, this means people using peer to peer services may need to carefully watch their upstream usage. One interesting issue to consider is that modern digital cameras can easily produce pictures that are 3MB or more in size. Uploading a couple of hundred photos to a backup or printing service could rapidly eat up a significant part of your allowance if you're not careful.