Windows Live Calendar made its first appearance last Friday evening (PST), was available for a while, but then access for new account sign ups was turned back off (if you logged in to Windows Live Calendar while it was available, you can still get in). Launch day was expected to be yesterday, we even had a member of the Calendar team email us: "...we’re not releasing officially until Monday". However as of Tuesday morning at 8:30am pst www.calendar.live.com is still reverting to the old MSN Calendar in Windows Live Hotmail.
Hopefully Calendar will be up and running soon, we'll hear from the long sequestered Calendar team (with a blog to keep us informed of these types of things? hint, hint), and all will be well again. In the meantime, you can read about our first impressions, and keep your fingers crossed.
Update: It's up now! :)