I noticed this during The Wright Stuff this morning. Took me a while to spot it, though, so it obviously isn't too obtrusive. I do wonder why it is necessary, though. Analogue terrestrial channels don't need them, as the transmitter identifies which channel it is, which in turn displays on the TV when you switch on the channel. One could argue that they aren't even needed for digital terrestrial/satellite/cable as all of these platforms have banners which identify which channel it is, in a similar way to analogue.