Android Market will download all your apps and paid apps to your new device. Android Market is based on your Google account.
If your phone is rooted you can use titanium backup to save your progress to drop box directly.
How is it when people change phones? Apple: Sync your phone: all SMS, contacts, layout, apps are synced.
I bet that is not the same with Android. I can't just plug in my new Nexus and have all my contacts, layout and so on transferred.
How about Apps? If I buy 100 Android apps on my HTC and change to a Motorola: will the apps automatically transfer? Will they even work? How do people sync their stuff? Dragging folders in explorer?
For android Contacts, email, calendars, books, pictures, docs and apps are synced automatically when you provide your google account.