Microsoft must have done something right with the launch of Outlook.com, their new e-mail service designed to replace Hotmail and lure users away from Gmail. In a mere six hours, Microsoft has said that Outlook.com saw 1 million users sign up. These sign-up numbers were Tweeted by @Outlook six hours after the service was first announced.

Users of the new service will receive a new domain for their e-mail address--"@outlook.com"--which replaces the older "@hotmail.com." Users can, however, upgrade now and keep their current e-mail address. Eventually, the service will feature Skype integration, something designed to rival Google's Gmail and Talk integration.

All that remains to be seen is how many users will change from Hotmail over to the new service. Microsoft needs to create enough buzz around the new service in order to keep users from jumping over to Gmail. Google has the lead with 425 million users, while Microsoft has just 350 million at last count.