All you need is some house shoes or socks and whatever you are going to wear going home. The baby would need outfit to go home in and the hospital provides you with everything else.
To be honest, I packed WAY too much for my first hospital stay! I would suggest music, videos, maybe a crossword/something to divert you during waking hours that aren't absorbed with staring at your little one, toiletries, a pillow (I'm picky)...
I would not pack much clothes and those you do pack, pack your comfiest. I packed clothes for each day, including pjs, then realized it was much easier to wear the hospital gowns and to keep baby swaddled in a hospital blanket until the "big trip home". I did miss the creature comforts though - they have meals, etc provided but who knew it was tough to secure chocolate peanut butter cups through the hospital kitchen? :)