A new video accidentally posted to YouTube reveals details of the newly redesigned version of Google’s popular mail service Gmail.

A Google spokesperson said that the video was leaked and it wasn’t supposed to be viewed yet.

“Oops, you weren’t supposed to see that,” Google’s Andrea Freund told Business Insider. “Stay tuned, we’ll be sharing more info on Gmail’s new look soon.”

In the one-minute, 27-second video, Google Gmail User Experience Designer Jason Cornwell outlines some of the more noticeable changes to the design and functionality of the mail service.

“We’ve been hard at work to update Gmail with a new look, and I’m excited to share with you the biggest improvements. To start, we’ve completely redesigned the look of Gmail to make it as clean, simple and intuitive as impossible,” Cornwell said, wearing a red “Google” tee shirt.

The new version of Gmail adapts to fit in any size window, and if users prefer a specific display density they can set that as well, he pointed out. Google has also changed Gmail’s chat and label functions, giving users the option to customize their preferences.

“Some people use a lot of labels, others chat a lot. You can now adjust the size of the label and chat areas to meet your needs. Even if you do nothing, your Gmail adapts to you,” Cornwell explained. “The new look allows themes to really shine. We’ve updated many of them with new, high-resolution imagery.”

Conversations with Gmail have also been redesigned, to improve readability and to feel more like a real conversation, he said. Google has also added profile pictures, so you can see who said what.

“Searching is at the heart of Gmail; the new search box makes it easy customize your search and find exactly what you’re looking for. You can also create a filter right from the search box,” Cornwell concluded.

Gmail now looks similar to Google’s redesigned version of Google Docs, Business Insider said.

Although Gmail holds a negligible market share in comparison to Microsoft’s enterprise email business, it could emerge as a threat to the software giant in the future, according to a report in U.K.’s The Register.

Although Google’s Gmail only occupies a small slice of the enterprise email arena, it makes up nearly half of the cloud email market, which researchers at Gartner expect will grow rapidly in the next ten years, as reported by the Register.

Analysts say Google’s email service is the only one to really appeal to enterprises in the last few years, apart from Microsoft Exchange, as other offerings, such as Novell GroupWise and IBM Lotus Notes/Domino, are losing momentum, TechZone360 reported. Cisco has also dropped its cloud email venture and VMware’s Zimbra is only just starting to look at businesses.