It's important to prepare in advance for buyers' expectations about what you'll leave behind. As a general rule, you'll be expected to leave behind all "fixtures," defined in most states as things that are affixed, fastened to, or an integral part of the home or landscaping. For example, lights and their shades (the sort that can't be unplugged and carried away), built-in dishwashers and other appliances, window shades, curtain rods (and sometimes the curtains), built-in bookshelves, and all trees, plants, and shrubs with their roots in the ground instead of in pots are all normally considered fixtures. No matter how good they make the house look, if you don't want the buyer to keep them, replace them before you start showing the house.
Also realize that buyers may associate some items that aren't technically fixtures so strongly with your house that they won't be happy at you carrying them off -- for example, a backyard statue that's so perfectly placed in the center of a brick circle that you'd think it was a permanent part of the landscaping. The buyer may name such items in the purchase offer to make sure you leave them behind (or to start negotiations over them) -- or may assume they come with the house and raise a fuss on closing day when they've been moved. Take a good look at what you plan to move. If anything falls into the category of "A buyer may fall in love with this and assume it comes with the house," decide now whether to move it before the sale or to buy a replacement.