Cards App for iOS
Phew. Busy day of updates if you're an Apple fan(atic).
Cards (also free in the App Store, also requires iOS5) is available for download.
Cards lets you create a postcard from your own photos and text, using Apple's provided templates, which Apple then mails out for you. With a custom designed stamp from Apple, naturally. All for $4.99 per card.
The cards look beautiful, as you would suspect from Apple. But it is a funny app/service to release when everything else Apple is doing is pushing people away from real items into digital.