Abstract description of the Address Book

I've found on the, Msn Fanatic forums, an USA Patent Office application for a "server based address book".

Now, apart from the dubious patentability of such things, I read there an useful paragraph:

[0028] In order to manage this process, the auto update engine 115 generates and modifies a status flag which is stored in the contact information in the AB owner's contacts. The status flag, referred to herein as "ContactType," may be set to the following states for a contact in the AB owner's contacts: [0029] "Regular"--when there is no automatic update relationship between the AB owner and that contact; [0030] "Live"--when there is an automatic update relationship between the AB owner and that contact (i.e., the AB owner will receive updated information when that contact updates his or her profile) and at least one update has been received from the publisher's profile; [0031] "LivePending"--when an AB owner has requested to receive automatic updates for a contact, and is waiting for authorization by the contact; [0032] "LiveRejected"--when the AB owner has requested to receive updated contact information from that contact, but that contact has denied that request; and [0033] "LiveDropped"--when there was an automatic update relationship between the AB owner and that contact, but the contact has rescinded that relationship. 

Which is the description of the <Contact Type> SOAP tag in every contact described by the Ab Find All SOAP response:

                    <Contact>
                        <contactId>a GUID without curly braces</contactId>
                        <contactInfo>
                            <locations>
                                <ContactLocation>
                                    <contactLocationType>ContactLocationPersonal</contactLocationType>
                                    <city>Rome</city>
                                    <country>Italy</country>
                                    <Changes />
                                </ContactLocation>
                            </locations>
                            <annotations>
                                <Annotation>
                                    <Name>AB.Profession</Name>
                                    <Value>Reverse Engineer</Value>
                                </Annotation>
                            </annotations>
                            <contactType>Live</contactType>
                            <quickName>Contact Name</quickName>
                            <firstName>Contact</firstName>
                            <lastName>Name</lastName>
                            <passportName>email@address.com</passportName>
                            <IsPassportNameHidden>false</IsPassportNameHidden>
                            <displayName>Contact Name</displayName>
                            <puid>0</puid>
                            <CID>very long number here</CID>
                            <BrandIdList />
                            <IsNotMobileVisible>false</IsNotMobileVisible>
                            <isMobileIMEnabled>false</isMobileIMEnabled>
                            <isMessengerUser>true</isMessengerUser>
                            <isFavorite>false</isFavorite>
                            <isSmtp>false</isSmtp>
                            <hasSpace>false</hasSpace>
                            <spotWatchState>NoDevice</spotWatchState>
                            <birthdate>1984-01-01T00:00:00-07:00</birthdate>
                            <primaryEmailType>ContactEmailPersonal</primaryEmailType>
                            <PrimaryLocation>ContactLocationPersonal</PrimaryLocation>
                            <PrimaryPhone>ContactPhonePersonal</PrimaryPhone>
                            <IsPrivate>false</IsPrivate>
                            <IsHidden>false</IsHidden>
                            <Gender>Unspecified</Gender>
                            <TimeZone>None</TimeZone>
                            <PublicDisplayName>Contact Display Name</PublicDisplayName>
                            <IsAutoUpdateDisabled>false</IsAutoUpdateDisabled>
                            <PropertiesChanged />
                        </contactInfo>
                        <propertiesChanged />
                        <fDeleted>false</fDeleted>
                        <CreateDate>2009-03-21T14:10:00-07:00</CreateDate>
                        <lastChange>2009-03-21T14:10:04.89-07:00</lastChange>
                        <CreatedBy>7</CreatedBy>
                    </Contact>

Very, very interesting pictures are available by clicking on the blue "Images" button.

There also are descriptions of Gleams and other mechanisms used by Live Messenger.