Yes, depending on what you plan to use it for. When I smoke, I'll occasionally catch the drippings and save the carcass for stock, which I'll freeze. But I use it primarily for sauces (think BBQ sauce base).
Yes. I smoke my turkey over cherry wood and always use the carcass to make stock. I use Ruhlman's oven method [ruhlman.com.] It is one of the highlights of the season. It makes a particularly good Pasta e Fagioli soup, and of course, a wonderful veloute for turkey pot pie.