My wife is (finally!) ready to upgrade from her LG Quantum WP7 to a Lumia WP8 device. But she's mentioned she wants to keep her Xbox Music Pass on the WP7 device and use it as a music player. Since the Music Pass is tied to her Microsoft Account, what do I need to know to make this work?
As you said yourself, an Xbox Music Pass is tied to a Microsoft account, not to any specific device. You can have up to 4 devices (including WP7 phones) associated with your Pass. So as far as I can see, your wife should be able to just sign in with her MS account on the new Lumia and keep enjoying her Xbox Music Pass on both phones.