This report is based on usability studies with real users, reporting how they actually used a broad variety of iPad apps as well as websites accessed on the iPad.
We are making this report available for free to support our loyal audience of usability enthusiasts by providing them with early empirical data about iPad usability. This report is less thorough than our normal research reports and does not contain as many detailed and actionable design guidelines as we usually provide. We decided to publish the report anyway (as a donation to the community) because all experience from the last 30 years of usability shows that early usability findings have disproportionally large impact on design projects.
via Usability of iPad Apps and Websites: First Research Findings.