I am loving IOS 7 and there is a great new addition to Find My iPhone – you cant reflash the phone while it has a valid Find My iPhone enabled. This is a huge improvement! Check out the email I just got from iCloud:
Congratulations on your update to iOS 7. As an iCloud user, part of your upgrade includes new features built into Find My iPhone that make it harder for anyone else to use or sell your device if it is ever lost or stolen.With Find My iPhone turned on in iOS 7, your Apple ID (karl@asktheadmin.com) and password will always be required before anyone can:

Turn off Find

My iPhone on your device.

Erase your device.
Reactivate and use your device.

There is nothing you need to do except to keep Find My iPhone turned on and remember your Apple ID and password. For more information, read the FAQ.Note: As always, if you plan to give your device to someone else, make sure to erase all content and settings before transferring it to the new owner. This will remove the device from your account and allow the new owner to activate it. For more information, read What to do before transferring ownership of your iPhone, iPad, or iPod touch.

The iCloud Team