Late last week, retailer Eplehuset (Apple House) suspended pre-orders all together when they sold out. A message posted to their site states that those who have already placed orders will have their spot in line reserved, while others are out of luck. "We have chosen not to receive more pre-orders for now," the site says via Google Translate, "we will contact you as soon as we know anything more."
Additionally, iPod1 reports that retailer Humac has suspended iPad pre-orders. We don't have any stats on which model is being ordered most often, but Electronista suggests that it's the 64GB iPad with 3G model. It's also notable that most countries aren't offering pre-orders yet (including Apple itself in the US), so there's no way to gauge if the Norwegian customers' enthusiasm is typical.
While e-readers like the Nook and Kindle generated a lot of pre-release buzz, tablet computers historically haven't sparked a blaze of enthusiasm in the wider market. If these retailers' experiences turn out to be typical, Apple will have a real hit on their hands (and in ours) with the iPad.