Apple has finished smoothing out its Xcode releases with version 4.4.1, which finally brings Xcode out as a standalone app. Instead of just including the developer tools (such as legacy simulators and optional command-line tools), it now has sectioned those off into a separate downloads preference pane.
This is a smart way to go about things. It allow for Xcode to be easily updated from the Mac App Store. You can get Xcode 4.4.1 for free, though remember that actually submitting apps or developing on iOS will require a developer subscription, from the Mac App Store.