The iPad's success has taken many tech enthusiasts by surprise, and apparently, it's selling better than Apple first expected, too. With sales of the tablet climbing to 500,000 in the first seven days, Apple says demand will likely exceed supply over the coming weeks. In addition to shipping Wi-Fi models, the company is trying to manage an untold number of preorders for the 3G-equipped iPads, which should launch later this month.

Due to this "surprisingly strong U.S. demand," Apple has decided to postpone the iPad's worldwide launch by one month. It's now set to go global toward the end of May, and the company will announce international pricing as well as begin taking preorders online on Monday, May 10.

The tablet will eventually appear on shelves in countries including Australia, Canada, France, Germany, Italy, Japan, Spain, Switzerland, and the UK. For what it's worth, the cheapest Wi-Fi model starts at $499, while the most expensive 3G version is $829, so expect similar pricing in your region.