While the iPad looks like it is going to be successful, I think that there is a question over how the market for iPad Apps will develop. Apps for the iPhone are a stunning success that caught many by surprise. I recall a post in TechCrunch when the iPhone App-store was about to be introduced. Using numbers that were probably leaked from Apple, the column predicted a substantial and valuable market for iPhone apps. The commenters were full of scorn, suggesting that the idea of anyone paying money for little apps was ridiculous. Apple showed us just how it could be done.
On the other hand we have the iPad. Apps for the iPhone make sense because of its small screen. Each app makes the best use of the limited screen space for its own dedicated purpose. The iPad has a much larger screen where the browser with scripting and plug-ins can support most of the experience. Therefore the need for specialized apps is less compelling.
There will still be iPad apps. For example I expect games to do well. However, media companies hoping to monetize their content through subscriptions have a tricky tightrope to walk. Most media companies now make their content available for free on the internet supported by advertising. They cannot afford to withdraw this content completely, but on the other hand if they want to monetize through the iPad, they have to provide a value added experience through their app if they expect to get people to pay. I look forward with interest to see how this all plays out.
Update: TechCrunch just posted on how magazines might work this issue with video on the cover.