The iPad is redefining the very concept of a "magazine." A new iPad application, Flipboard (co-created by a former Apple engineer) automatically converts your friends' Facebook and Twitter updates and recommendations into easy-to-navigate "digital pages" that compile the information into one beautifully designed package — and urges you to return the favor. (See demo video below.) It's rare to find an application that looks this "attractive and feels natural when you interact with it," says Alan Henry at PC Magazine. Flipboard is the first app that truly delivers on "the promise of the iPad as a media platform." Well, not quite yet, warns Ben Patterson at Yahoo! News. "Cool though it is, Flipboard is still very much a work in progress." It's being characterized as a personal magazine, but (so far) you can't even "prioritize updates from specific Facebook or Twitter users." Here's a preview of the free app: