From the Windows Live ID team blog —“CardSpace is a new way to sign in securely and conveniently into websites. And now you can use CardSpace with Windows Live! Using CardSpace with Windows Live means you don’t use a password to sign-in to websites which accept Live ID credentials. Instead, just send your CardSpace card to Live ID to identify you and use your Hotmail or Windows Live Spaces. And it is incredibly easy to use CardSpace with your LiveID. Just Follow this link (here) to get going in minutes!”
If you are using Windows Vista, you are all ready to use CardSpace cards! If you are on Windows XP (or Windows 2003), you will need couple of quick steps. Go get IE 7.0, our newest and coolest browser, if you don’t already have it and install .Net 3.0 with CardSpace support. Follow these two quick steps to add an Information Card to your Live ID. To install these components and add an Information Card to your Live ID account, visit the Windows LiveID Information Card management page. Also go to that page to make changes to CardSpace cards linked with your LiveID.
Once you’ve added an Information Card to your Live ID account, sign in using the Information Card. You will be amazed at how easy it is! BTW, that Windows Live ID CardSpace support is still a “Beta”. We are still working on it and know a bunch of things that could be better. But do let us know your wish list; it is always good to get feedback.