WebIS have released a single preview screenshot for Pocket Informant for the iPad. We don't know much about Pocket Informant on the iPad yet, but this screen shot shows the potential for a PIM on the iPad.
For those of you unfamiliar with Pocket Informant, it's an all-in-one personal information manager. It's currently available on multiple platforms, including the iPhone. And is very highly regarded. If the built in Calendar just doesn't do enough for you, you should look into Pocket Informant.
We took a look at the iPhone version a few months ago -- you can read that review to see how much we admired the app on the iPhone. And I think we can expect more of the same on the iPad version.
What we do know is the Pocket Informant for the iPad will be $15 when released. It will be a separate app from the iPhone version to help speed the development of each app. Exactly when it will be released, we don't know. But it can't be soon enough!