As Andy said (yep, I'm still agreeing with you my freind), the only thing you have to do is make sure you use a meat thermometer to avoid overcooking the bird.
People are taling about pre-basted turkeys. I believe what they mean is self-basting turkeys. These birds have a broth injected into them, adding flavor, weight, and extra flavor to the meat. As the flesh is heated, some of those juices ooze from the injection points and run down the skin, basting the bird.
The advantages for the company that injects the birds are, first, cooks believe that the turkey will automatically be more succulent and taste better. It's a bit of advertizing hype if you will. Second, the bird will weigh more, fetching a better price, and more profit for the processor.
I still inject my turkeys, to add aditional flavors, let it sit for a while to allow the injected juices to distribute themselves, and make sure to ignore the pop-up timer, as waiting for the timer virtually gaurantees a dry, overcooked turkey.
As far as roasting breast-side up, or down, it really makes no difference to the meat, though the skin is definitely better when roasted breast-side up. Also, a tent of foil helps make sure that the dark meat will be done at the same time as the white meat, as the dark meat cooks a bit faster. Just remove the foil for the last 20 minutes of cooking time so that the skin will brown properly.
Seeeeeeya; Goodweed of the North