Struck me a couple of times recently that the 18:30 spot has had the continuity announcer follow a broadcast with the fact the programme can be purchased on iTunes.
I feel fairly sure it wasn't just one show, but on different nights in recent weeks, so wonder if this is a new policy... Licence fee pays for it first, and then they grab payment again from the same licence fee payers if they want to download it to keep...
Maybe it's a result of the BBC squandering nearly 100 million on the "Digital Media Initiative"... they have decided to charge for downloads.