As promised, Apple's taken a bold step into the cloud services arena today with the introduction of iCloud. Steve Jobs took the stage not only to tell us all why the old method of wired syncing doesn't work but why Apple's throwing MobileMe out the door. That's right, Apple's thrown away the core MobileMe apps — contacts, calendar, and mail — and built them from the ground up with iCloud. So, how does it all work? Basically, the new service stores your content and then pushes it to all your Apple / iOS devices wirelessly. Or more simply, email, calendar and contacts are now synced through "the iCloud." And since MobileMe is no more, all three of these services are now free. Yes, free.

However, those aren't the only apps that work with the new iCloud service. Apps, iBooks, Documents (Pages, Keynote, Numbers), iTunes, and Photos will work as well. The first three are relatively simple: your apps, books, and documents will be pushed to your devices without ever manually syncing them through iTunes. In many cases, the files / apps will appear and you will be able to choose if you want to download them. However, the Photos and iTunes implementations are pretty specific. With Photos, Apple's added a feature called PhotoStream to various photo apps, including iPhoto and the Photos folder in Windows, that lets you view pictures from your various devices. Apple will store the last 1,000 photos you've taken for 30 days on its own servers.

As for iTunes, we have broken down everything you need to know about the new service here and just did a short hands-on with it. It not only syncs all your tracks across devices, but also includes a new service called iTunes Match, which will match the songs you haven't purchased with iTunes with 256 kbps AAC DRM-free versions. Apple will also offer its own Backup app, which will automatically backup music, apps, pictures, and books once a day — although, it looks like it will only work over WiFi.

All of the services, save for iTunes Match are free, and Apple will be giving consumers 5GB of space for mail, documents, and backup (apps, photos, and books don't actually tap that storage). There will be an option to purchase more storage space, but pricing options will be announced when iCloud is officially available in the fall. iCloud is, however, available to developers today.

Update: iTunes in the Cloud beta will be rolling out to all iOS 4.3 users.