In a post on the Outlook blog, the company said all Hotmail users have now been transfered over to the new service, all in the six weeks since Outlook came out of public preview in mid-February.
The company said it now has 400 million active Outlook users, which is almost halfway to its eventual goal of amassing 1 billion regularly used accounts, while building 'the best email service in the world'.
The company has been very active as it moves towards the target, integrating Skype calls, launching a new Android experience, an Outlook calendar, and two-step security verification.
Seriously deep SkyDrive
While Hotmail is now strictly past tense in Microsoft's world, the company again moved to ensure users they'll still be able to log in with their old email address.
Also, as part of its self-administered pat on the back, Microsoft also announced deeper SkyDrive integration and is now allowing users to attach files and photos directly from the compose email page.
The blog post explained: "Today, we're excited to release the direct integration of SkyDrive into the Outlook.com compose experience. When you're sending an email message, you can select files from your SkyDrive and we'll automatically turn those into the right thumbnails with links that have the right permissions tied to people that receive the email.
"When you insert pictures from SkyDrive, you automatically get a beautiful photo mail. And it's easy to edit the message, and add or remove files and pictures right from the new message compose experience. This new integration is starting to roll out today and will be available worldwide in the coming weeks."
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A technology journalist, writer and videographer of many magazines and websites including T3, Gadget Magazine and TechRadar.com. He specializes in applications for smartphones, tablets and handheld devices, with bylines also at The Guardian, WIRED, Trusted Reviews and Wareable. Chris is also the podcast host for The Liverpool Way. As well as tech and football, Chris is a pop-punk fan and enjoys the art of wrasslin'.