Yes, the iPad will automatically update contacts and calendar information wirelessly from your MobileMe account. MobileMe push email is easily accessible via the Mail application on the iPad.
The iPad works with other MobileMe features such as Remote Wipe and Find My iPad. MobileMe will also wirelessly sync your web bookmarks on the iPad.
The MobileMe iDisk and Gallery apps that are available for iPhone have been released on the iPad, allowing access to MobileMe subscribers' content.
In a related note, the iPad SDK does include support for a shared file directory that can mount to a Mac or PC for transferring documents. This directory is accessible by iPad applications.
MobileMe includes 20GB of space and costs $99 for one year.