Microsoft's Windows Live ID team has started a blog to communicate information about the new product, which is a replacement/upgrade for the Passport service. From the inaugural post:

"Windows Live ID is the upgrade/replacement for the Microsoft Passport service and is the identity and authentication gateway service for cross-device access to Microsoft online services, such as Windows Live, MSN, Office Live and Xbox Live.  Is this the authentication service for the world?  No   It's primarily designed for use with Microsoft online services and by Microsoft-affiliated close partners who integrate with Windows Live services to offer combined innovations to our mutual customers.  We will continue to support the Passport user base of 300+ Million accounts and seamlessly upgrade these accounts to Windows Live IDs.  Partners who have already implemented Passport are already compatible with Windows Live ID.
 
"Windows Live ID is being designed to be an identity provider among many within the Identity Metasystem.  In the future, we will support Federated identity scenarios via WS-* and support InfoCards.
 
"For developers we will be providing rich programmable interfaces via server and client SDKs to give third party application developers access to authenticated Microsoft Live services and APIs.
 
"Over the next few weeks as we complete our deployment, you will see the Windows Live ID service come alive through our respective partners sites and services.  The first thing you’ll notice as early as today is that the word Passport is being replaced by Windows Live ID.  But isn't a rebranding exercise -- there is stuff going on under the hood.  This will be more understandable in the coming weeks and months when you start seeing the new, exciting Windows Live sign-in UI.  Not only is the page load time significantly reduced, but you will see some really cool innovative features that we’re sure you’ll love :)"

I'll likely be writing here on this weblog about Infocard (which I have early some experience with), authentication and other related topics, since I have a professional connection to all of the above. Glad to see the Live ID team getting their blog start - this is the beginning of what should be a great phase of changes and improvements in the area.