Are you confusing Geordie wth Cockney? Lots of modern urban accents replace [t] with a glottal stop, but I don't think people in Newcastle are more likely to do that than people from any other big city. Or are they? Can someone clarify?
By the way, I am getting very bored of The Register's tedious images of open-mouthed women that hev nowt to dee with the story, like.