Microsoft has added Xbox 360 friends-list support to Live Messenger - but it doesn't appear to work in Europe at the moment.
Last night Xbox Live's Major Nelson updated his blog with news of the change, which introduces a button to the tabs bar that allows you to view your friends' status information and click through to their profiles.
But, judging by the responses on the comment thread and our own experiences, it's not working in Europe. Nelson concedes it's "for US and Japan passport accounts only", but he also said that "it is purely up to the regional Windows Live Messenger teams if they want an Xbox tab", so we got our hopes up anyway. If your regional version of Live Messenger has the tab, do let us know in the comments.
Not to worry though either way, because you can always use free friends-list tool XBList instead.