Starting today, YouTube will look dramatically different for everyone. That’s because the Google-owned video website will be rolling out its redesign to all users over the next few hours — the rollout should be complete by 7:00 p.m. today.

You may have already seen elements of this redesign: The actual interface was revealed two months ago. Since then, though, YouTube has tested, iterated and made changes to the new design. Today, however, it feels comfortable enough to roll it out to its millions of daily viewers.

Here at YouTube’s headquarters in San Bruno, California, we were briefed on what users should expect starting today and the thought process that went behind each of the changes. Here’s some of what we learned:

The New YouTube: Leaner and Less Cluttered

During its research, YouTube analyzed data on what users wanted on video pages, as well as what features these users interact with (e.g. comments, subscriptions, rating videos). However, at least 37% of YouTube’s users simply don’t want or use these these features; if they could just have a webpage with a title, a giant video and a search box, they’d be ecstatic.

The new video pages are very similar to the redesigned pages revealed two months ago: five-star ratings have been replaced with a thumbs up-or-down system, the “subscribe” button has been moved into a more prominent location on the top of the page and video descriptions have been moved from the right hand side of the video to under it.

During our briefing at YouTube HQ, the company demoed some of the more subtle new features. YouTube has made accessing descriptions, view counts and video stats easier by creating a hover effect (you will see a blue highlight when you hover over descriptions and the view count) and making the entire area clickable. The view count is now placed in a larger font and emphasized more strongly because it’s one of the most critical components of the video page.

The change in how videos are rated makes perfect sense to us (nearly 90% of users clicked “five stars,” essentially rendering a five-point scale useless), but the company has even thought about details such as the size of the like and dislike buttons. You’ll notice that the “like” button is wider than the dislike; this is based on how the average person uses these buttons.

Navigation Simplified

The masthead has also been massively pared down — it’s thinner and focused almost entirely on the search box. YouTube is, after all, the world’s second largest search engine, only beaten by Google itself. You’ll also notice interface changes when you perform searches.

Focus has also been placed on improving advertising and branding opportunities for its top content creators. We were shown an example of a YouTube star transforming her username into an image that definitely pops out to the eye. This all happens on the video page.

The navigation to the next video has also received attention. YouTube doesn’t want you to leave its website until “you’ve run out of videos to watch, which will hopefully never happen.” To that end, the new system works more like a playlist, where videos will play one after another. Even when you perform a search, video playing won’t be interrupted. Autoplay features have also been added.

Finally, expect changes to YouTube’s many mobile interfaces — Google-controlled ones (like the YouTube player on Android) will be changed in the next few weeks to reflect the new changes, while others like the YouTube iPhone player will take some more time.

The individual changes are small, but as a whole they are huge and very notable. YouTube’s trying to refocus its strategy toward stronger user engagement and keeping people on YouTube for longer. The pages run faster and feel less cluttered, so we’re fans. How the average YouTube commenter reacts to the redesign is anybody’s guess, though.