Microsoft has announced that Outlook.com, the new webmail offering it launched in limited preview last year, is officially launching worldwide to all. According to the company, it has already amassed 60 million users in 6 months. According to a report from Bloomberg, a third of that number is made up of people who switched from Gmail for their primary free email account.

Is Outlook.com better than Gmail? Let us know what you think.

“Since the service was released as a preview last summer, the team’s goal has been to provide the best email service possible, encouraging feedback from customers using Outlook.com,” a Microsoft spokesperson tells WebProNews. “Since then, the team has fine-tuned the experience in order to deliver modern email for billions of email users.”

“To date, Outlook.com customers have praised the inbox experience, with deeper social integration, 60% fewer ads and one-of-a-kind tools for managing newsletters, which make up as much as 80% of the typical inbox,” the spokesperson adds. “Outlook.com customers are also enjoying the SkyDrive integration, with more than half a billion photos and Office documents shared by Outlook.com customers via SkyDrive.”

Here’s a walkthrough of the features:

With the launch comes an automatic upgrade process for millions of Hotmail users, who will be transitioned to the Outlook.com experience. It will be interesting to see how current Hotmail users like the transition. Here’s what David Law, the director of product management has to say about the transition:

The upgrade is seamless and instant for people who use Hotmail. Everything from their @hotmail.com email address, password, messages, folders, contacts, rules, vacation replies, etc. will stay the same, with no disruption in service. When upgraded, they’ll also get all the benefits from the redesigned Outlook.com experience–a fresh and intuitive user interface, lots of new features and better performance. And we won’t ever make you switch your email address to an @outlook.com address if you don’t want to.

We expect all people using Hotmail to be upgraded by this summer. And for those that are excited to get the new benefits of the Outlook.com experience, there’s no need to wait. You can upgrade today by simply signing in at Outlook.com and we’ll take care of the rest.

Microsoft is also starting a huge marketing effort, though you could really say this already started with the latest “Scroogled” campaign a couple weeks ago. The company came out attacking a decade-old Gmail feature as it urged users to switch to Outlook.com.

Google users algorithms that serve Gmail users ads based on the content of their email messages. Microsoft is framing this as a privacy issue, though it scans emails itself for security issues (as does Google). No humans are reading your email, regardless of which of these services you are using.

Here are the ads in case you haven’t seen them:

The campaign itself has been the subject of a fair amount of criticism. It will be interesting to see how much of Microsoft’s ongoing Outlook.com marketing is slamming Google, compared to how much is simply promoting the product’s features.

The company is reportedly spending tens of millions of dollars on TV, online, print and bus advertising, amounting to what is reportedly the biggest-ever ad campaign for an email product [Bloomberg].

New users can get an @Outlook.com email address. Hotmail users, as their accounts are upgraded, will be able to send/receive email from @hotmail.com, @msn.com or @live.com addresses. Users of other services like Gmail or Yahoo Mail can set up a new @outlook.com address, and have their other accounts forwarded.

There’s a mobile set-up guide here.

What do you think of Outlook.com? Better than Hotmail? Better than Gmail? Will it help win a bigger chunk of Gmail’s market share? Will you be switching? Let us know what you think.