Well, on other smartphone platforms, you have your own Profile in the system. Making your own contact is redundant and can potentially interfere with things especially if you have a common name. Nevermind it's just one more contact taking up space in the list.
Originally Posted by dtboos
Blackberries and Android Phones have "My Profile" where you enter all of your personal information. iCloud also has a contact that is dedicated to you. This allows the phone to do things like Automatically Enter in Information (your choice), and it prevents things like the phone trying to automatically add your own IM Handle (which can be input into your profile) to your buddy list. It also allows you to set your own Profile Picture which will be used by default when you send your contact card to someone (via Email, MMS, etc.).
Theoretically anyone who has your Windows Live Handle can see your contact information if they are friends with you on Windows Live (assuming your profile isn't public, in which case they can see it anytime). Maybe that is the method by which Microsoft would prefer us to share contact information (or via Social Networks like Facebook or Twitter, whose information is aggregated on the phone via integration)?