Service Upgrade - Outlook Autodiscovery and Updates

Intro

Regular people and IT Pros alike need to be aware of the following requirements for Outlook, when connecting to the new Office 365 '2013'.  Taking action on these important points will go a long way to a smooth Service Update and keep regular people and IT Pros happy.

Outlook needs to be set to use Autodiscovery

Outlook 2007 and 2010 need to have an update installed.

Regular Person, You the User - A (reasonably) Non-technical explanation

Outlook needs to detect your mail server and mailbox automatically.  Its important. Not just for preparation for your service upgrade to the new Office 365 '2013' services.
Outlook needs to be set to configure itself automatically so that other mail and communication services work correctly.
These are services such as Out of Office, Mail Tips, Lync-Outlook integration (conversation history, calendar integration for available busy status etc.)
I won't give instructions about how to do this.  Contact your organizations technical support and make them aware of this article and the reasons for using Autodiscovery with Outlook.

IT Pros, Admins, Techs and Engineers - Technical explanation

Some businesses have manually set Outlook to use the server name because they wanted to improve Outlook start-up time or reduce the likelihood of users being prompted for login credentials.
However, if  all the most recent updates for Outlook have been installed and Desktop Setup has been run, Outlook should not often prompt for username and password.  The exception of course is if the account is locked or the password has been changed.

Outlook should be using Autodiscovery for a number of reasons.  Manually setting the server in Outlook means:

• Exchange Web Services that provide  MailTips, Out of Office, Lync to integrate with Outlook (conversation history, calendar integration, contacts) are picked up from the Autodiscover.  These services won't work correctly unless Outlook is using Autodiscovery to receive it's configuration.
• Mailboxes on Wave 14 may be load balanced and moved to different servers or perhaps even geographic locations.  Even with Wave 14, the server name might change.  A manually configured Outlook client will lose connection with the server at that point.
• Your Office 365 tenant will be receiving a Service Upgrade soon. Exchange Online will change to using a unique GUID for each users server setting.  This GUID will follow them around, where ever their mailbox is moved, load balanced or recovered to.  When the Service Upgrade starts, a user's mailbox will be assigned its new GUID.  At that point, a manually configured Outlook client will not receive the change and fail to connect to the new Exchange Online '2013' server.

Are you starting to understand why Autodiscover should be used?

Outlook updates

Outlook 2007 and 2010 need updates to ensure that it will connect to the new Exchange 2013 server using Autodiscovery.

Outlook 2007 - http://support.microsoft.com/kb/2596598

Outlook 2010 - http://support.microsoft.com/kb/2553248

There may be updates released later that supersede these ones, but this is what you currently need (at the time this post was written) to release to your network, using whatever means.
Small Businesses might prepare by having users running Windows Update and making sure they install all the Office updates recommended to them.  They may also need to log into the Office 365 portal and run the Desktop Setup Tool again.
Medium Businesses and Enterprises might perform a controlled, tested and managed approach of releasing these specific updates, using something like WSUS or System Centre Configuration Manager.

Read the about the administrator tasks here.

Don’t put off reading them, read them. Book the time out in your calendar and make sure you understand what applies to your environment.

http://community.office365.com/en-us/wikis/manage/office-365-administrator-task-wiki.aspx#Outlook2010

Review this task specific to Outlook Autodiscovery

http://community.office365.com/en-us/wikis/manage/correcting-autodiscover-and-dns-settings.aspx

Many thanks to Jaysen Wu, Office 365 Technical Support for "Manpower", for this information.
Pass this on to others who need to know. (No really, this is NOT a chain letter.)