Once WiFi syncing is enabled, the iPhone or iPad will still be accessible in the iTunes sidebar even when ejected. Better yet, the devices will also back up wirelessly to iTunes before a sync session, which provides a safety net of sorts for your device data. Note: Wireless syncing requires that iTunes be running. From my experience, that's not much of a problem for Mac users, but it might be more problematic on Windows, where iTunes can be resource-intensive.
Here's a helpful hint: If you keep your media selections to a minimum the first time you enable wireless syncing, you'll be able to use your device sooner, since you won't be waiting for a full-blown sync. Once that first iTunes sync takes place and wireless syncing is enabled, you can then go through and select the media you want. The next time the iPhone is plugged in to a power outlet (say, to charge during the night) it'll automatically kick-start an iTunes sync and copy everything over. By the time you wake up, all of your media should be on your iPhone.
As always, you can't sync more media than your device can hold. So if you have 100GB of music and movies, and a 32GB iPhone or iPad, you'll have to pick and choose.
Your new 'cord:' iCloud
As I noted last week, I think the arrival of iCloud is a bigger deal than the arrival of the iPhone 4S.
Basically, iCloud is a collection of services that backs up your data -- everything -- to Apple's servers automatically. Every photo, document, bookmark, contact, song, movie, video, ringtone, text message -- even the layout of your home screen -- all gets backed up.
iCloud scales up. If you have other devices, iCloud makes sure those devices receive your data, too, without you having to lift a finger. It's invisible.
iCloud starts with a free email address, and any device signed in with that address automatically syncs with Apple's servers. (MobileMe subscribers have to jump through a few easy hoops to move their account over.) It won't matter now which device you use to take a picture with, or where you left your presentation or whether you bought a song through iTunes on your iPhone, iPad or desktop Mac. All your content will sync with all your devices via iCloud, though of course you'll have to use iTunes to pick and choose how much of your digital media actually stays on your iDevices permanently. You won't, obviously, be able to sync an entire 100GB library of music on a 32GB iPhone. (iTunes Match will help in this area when it arrives later in the month, by allowing you access to your entire music collection via iCloud.).
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