1UP's Crispin Boyer was recently invited to visit Rockstar North's offices in Edinburgh, Scotland for an interview with Sam Houser. He's written a short but interesting article about his adventure (which includes the theft of some water!), and since Rockstar wouldn't let him take any photos from inside their studios, has filled the article with photos he took in Edinburgh.
There's no new info about GTA IV, but it's a fairly humorous article which you should definitely check it out if you have a few minutes.
Link: Grand Theft Auto IV Travelogue