Hi all,
For the new Office 365 service upgrade, there is one tip that I found useful during migrations, and that is how to manually configure an Outlook 2010 mail client (and this could be applied to Outlook 2007 as well). In the old Office 365 versions, if you did not have the luxury of having autodiscover setup yet, because maybe it was early on in the migration, there was a way of opening the Help-->About in the user's OWA setting and lookup the O365 server name. However, in the "2013" service upgrade, this is no longer the case, and in fact Microsoft support told me they do not support manually adjusting Outlook.
A workaround, however, is to use Autodiscover, but instead of typing in the user's vanity email address, use the user@tenantdomain.onmicrosoft.com. It will then autodiscover against the tenant domain, and when it prompts for username and password, put in the original user's User Principal Name, such as user@vanitydomain.com. This will allow Outlook to autodiscover without having to lookup any lengthy servernames.
Hope this helps someone who is trying to find settings to manually configure Outlook in the new Office 365.