Don't forget that the bub will probably be in with you for the first six months. My ds is 11 months and is still in with me.
For practicality, I would make sure your nursery has a cot, a mattress/futon/bed for someone to sleep in with the baby if needed (e.g. bad nights, colds etc), a decent supportive chair and a surface to put things on (e.g. bottles).
So long as you de-clutter it, you'll find it'll probably become like a 'real' nursery naturally when the baby comes.
My Dd had one picture of a gnome sitting on a mushroom on the wall of her nursery before she was born. It was one I'd had as a child, and I was sentimental about it 'watching over her'.
When she was born, she got a clutch of very random oversized stuffed animals. Now, a newborn really has no use for a large stuffed animal. If you put up a cheap shelf, you'd have an attractive place to display your more impractical gifts.
My SIL likes photos of family members in the nursery. That way, she can chat to the baby and tell them about great-aunt gertrude or whoever. It'll make the baby more receptive to these people when they meet them.
Books are nice too. There are lots of free ones floating around hvs offices - ask for the 'Bookstart pack'.