It would be really nice if you could set close friends and get a notification or email that it's their birthday and to see their wishlist. That way if you have a friend that you tend to forget it's their birthday but you're friends with them on steam you can send a game their way so you don't feel like you forgot their birthday and they'd never know you did! Even if it's just a "Hey, your friend's birthday is coming up! Would you like to see their wishlist?"