Looking for someone smart, independent, confident, good conversationalist, athletic, and has a nice relationship with her family. Easy going, positive, and going for what she wants in life are also great characteristics.
It is all pretty simple -- finding someone who makes your life better and more enjoyable because that person is a part of it. A good balance of things in common, and some things not so in common, also helps to keep things interesting. In the end, you need to communicate and really know that the person whom you are with is your best friend and will always be there for you.