Nayna and Rob have made it official with their post (http://winliveid.spaces.live.com/Blog/cns!AEE1BB0D86E23AAC!931.entry), Windows LiveID has added beta support for Information Cards and Windows CardSpace.

The way this works is identical to the way I described how to add cards to an existing website in my book. Through a management interface, you associate information cards with your core account, and the user is provided the option of signing in with either their information card or a password (as shown below).

All good stuff, and worthy of checking out.