That's probably right ppeatfruit although I was thinking about this yesterday after watching the Armando Ianucci programme, that IMO 90% of Dickens' comedy is in the narrative, which does not come across well in TV adaptations.
(I think PG Wodehouse is the same, it's Bertie's narrative voice which is brilliant, the plots and dialogue come a poor second, which is why even Fry and Laurie couldn't do them justice.)
So I think that adaptations of Dickens for TV tend to try to wring comedy out of the books by turning his quirky characters into over-the-top grotesques. Which is why I avoided Dickens like the plague for years, I thought all that over-acting and stick-on warts stuff was as naff as could be. But the books have so much else. At least this adaptation didn't have many awful grotesque characters.
My favourite bit of GE is when Mr Wopsle becomes an actor and is appearing in a play. Dickens doesn't say what the play is but when Pip goes to see it, it's clear it's the world's worst production of Hamlet. I loved it. Yet it would be so lame if they did it on TV, it works because of the way it is described. I am so looking forward to reading it again when I get to that bit of the book.