Steve K replied to me:
I gathered there had been some sort of poll of the general public to arrive at these - presumably we didn't hear about it in time to stuff the ballots?
Actually, no, I don't think so. As has been pointed out, it's more to do with what they can show clips of, and what their pundits talk about - possibly which they're most entertaining about. The Top Ten series has always been somewhat bizarre in its selections.
Oh well, maybe I misremembered - I thought they mentioned a vote, but I can't check any more because my tape is in the hands of the post office en route to Australia.