From the Microsoft press release Microsoft Launches Windows Live Hotmail Worldwide we learn

REDMOND, Wash. — May 6, 2007 — Microsoft Corp. today announced that Windows Live™ Hotmail^®, the successor to MSN^®
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As Windows Live Hotmail begins rolling out on May 7 and continues over the coming days, consumers will be able to visit http://www.hotmail.com to sign up for a new Windows Live Hotmail account. Current MSN Hotmail customers can also update their existing account to Windows Live Hotmail by logging into their account and clicking on the green Join Windows Live Hotmail button.
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Hotmail, is launching globally in 36 languages. The most significant upgrade for Hotmail since it pioneered the webmail industry in 1996,

• Outlook Connector. Available later this month in 11 languages worldwide, the new Microsoft Office Outlook Connector beta will enable people to view and manage their Windows Live Hotmail account from Outlook for free, with full contact, e-mail and e-mail folder synchronization.

Congrats to Omar Shahine, Reeves Little and the rest of the Hotmail crew for getting this release out the door. This has represented man-years of work from the team and lots of us across Windows Live. Also, free access to Hotmail for Outlook users has been long overdue. I'm glad we've finally given this feature to our users. Kudos all around.

You can read more about the release from Omar in his post And We've Shipped and from the Windows Live Hotmail team's blog post It's Here and the Fun Has Only Just Begun

PS: Liveside has some news about the other Windows Live mail product in their post Windows Live Hotmail launches; "Windows Live Mail" to succeed Outlook Express and Windows Mail