[Neil Jones]

Like I say - early instalment weirdness.
Early Pointless had all the banter chopped out of it, until Alexander Armstrong noticed and said it probably should be kept (and of course they changed the basic format of the game in the process).

Bullseye is probably the most obvious example of early instalment weirdness that comes to my mind (the first series is totally out of whack in many ways compared to what followed), but most tweaks of this nature tend to be relatively subtle, as seen above with Only Connect (which was more green initially, had the "walk" to the podium for the Connecting Wall and of course had Greek letters (which apparently were "too pretentious" and generated complaints (apparently), so they swapped them for Egyptian Hieroglyphs instead)

If something changes channel it doesn't always mean it will be majorly different - Eggheads moved to Channel 5 and AFAIK aside from some adverts it's mostly the same.