The method for syncing iOS devices hasn't changed much, but you'll access them slightly differently. If you have the sidebar displayed (View > Show Sidebar), your iPhone, iPad, or iPod will display there as before, but if you dont use the sidebar, you'll access your iOS devices from a button at the top right of the iTunes window.
If you have, say, three iOS devices connected, the button will be labeled 3 Devices. Click it to see your devices, and then click one of the devices to access its syncing screens. These are much the same as before, though iTunes 11's Helvetica font makes them seem less airy. Small changes include displays of your devices current battery charge and of Install/Remove options instead of checkboxes for syncing apps to iOS devices.
After youve applied any settings you want, click the Done button to return to your iTunes library.
iTunes in the Cloud
iTunes 11 blurs the distinction between what's on your computer and what's in the cloud. If you check Show iTunes in the Cloud purchases in the Store preferences (it's activated by default), you'll see any music or video content that you've purchased from the iTunes Store in your iTunes library, whether you have physical copies of it on your hard drive or not. This differs from iTunes Match, where you can store your entire music library in the cloud; what you get here is just the addition of any items you may have bought and deleted.
This new display can be more of a hindrance than a blessing. Do you really want to see all of the free singles you've deleted after listening to them once? You can get rid of these items, but the process is slow: Go to the iTunes Store, click Purchased under Quick Links, and find the tracks that you don't want to see. In Album view, hover your cursor over an album and click the X icon located in the upper left corner. Doing so removes the album from your Purchased list and from your iTunes library. (To restore an item, go to your account in the iTunes Store, select iTunes in the Cloud > View Hidden Purchases, find what you want, and click Unhide.)
The new iTunes makes no visible changes to iTunes Match -- most significantly, no change to the 25,000-track limit. I deleted my entire iTunes Match library to start from scratch, and ran into the same problems I've encountered since the beginning, with some albums matching partially, but not matching on one or two tracks. Any tracks that didn't match in the past also didn't match this time around.