The Delete Contact button is there and works find if you use Contact app. However, if you pick a message from Messages app, click Details in upper right corner -> click i for Info -> click Edit, everything is the same except you don't get the Delete Contact button. Why is this, why?? How many time you you've finish a whatever business with someone you probably don't need to contact anymore and you now need to delete it from your contacts. And you find out you cannot do it? WHY WHY WHY?