If you've still been using the "old" Twitter, you won't be for long. The site announced late yesterday that it would be shutting the virtual doors on the "Old Twitter" this week, requiring everyone to embrace the "New Twitter" this week.

Curious what the difference is?

The "new" version of Twitter lets you navigate between @mentions, retweets, searches and lists from above your timeline. Pictures, video, and other media content is also now viewable directly on Twitter, so you don't have to click on a link in a tweet to check out that YouTube video your friend just tweeted.

The new version also shows "related content" with tweets, so you can learn a little bit about the people or things mentioned in a message, and gives you access to a "mini profile" where you can read someone's Twitter bio and their last few tweets without having to visit their actual profile page on the site.

The New Twitter has been available for quite some time, so unless you opted out of using it – you probably are.

Are any of you unhappy you're going to be required to use the new Twitter? What do you prefer about the older version?