Ubuntu 13.04 is here, and it's packed with new features to improve the Unity desktop including more social media integration, some new lenses in the Dash, and a significant speed boost.
Ubuntu 13.04 builds off many of the new features from its LTS (long term service) predecessor, improving on new features and bringing a few extra goodies to the table. Here's what you'll find.

Better Social Media Integration

What's New In Ubuntu Linux 13.04 “Raring Ringtail”
Ubuntu's Online Accounts preference pane has some handy new features. Now, when you add an account (like a Facebook or Twitter account), you can choose which apps on your system have access to it. Want Shotwell to access your Facebook photos, but don't want Empathy using it for Facebook chat? You can turn it off here with the flick of a switch.
The Dash also has a new Social lens (see the top image in this post), which allows you to see status updates from the friends you follow in your integrated social media apps. It also gives you notifications of new messages or mentions coming in, which is kind of cool.

New Window Management Options

What's New In Ubuntu Linux 13.04 “Raring Ringtail”
Ubuntu 13.04 added a few cool tricks for handling a ton of open windows. If you have a bunch of Firefox windows open, for example, you can hover over Firefox's icon in the dock and use your scroll wheel to cycle between windows. You can also just right-click on the icon to switch to a specific one.
The Workspaces feature is no longer enabled by default,but you can turn it on in Settings > Appearance. The new dock icon shows what workspace you're currently using, which is a small but handy addition.

A New, Social Photo Lens

What's New In Ubuntu Linux 13.04 “Raring Ringtail”
In addition to the new Social lens, you'll also find a new Photo lens in the Unity Dash. This contains images you've imported into Shotwell as well as photos on any social networks you've enabled in Online Accounts.

Improved Sync and Bluetooth Menus

What's New In Ubuntu Linux 13.04 “Raring Ringtail”
Ubuntu One users will see a new and improved menu in the menu bar, with one-click options to share a file, see your current transfers, and more.
If you have Bluetooth, you'll also see some small improvements in its menu bar dropdown, including big one-click switches to turn Bluetooth on and off.

Other Minor Appearance Changes

What's New In Ubuntu Linux 13.04 “Raring Ringtail”
Canonical has also made a few minor cosmetic changes around the desktop. Window snapping now has a new animation that shows you where the window will appear, the dock has a few new icons, and other small items have new fade animations around the UI. Unity also has a new shutdown menu more in tune with the rest of the interface.

Better Performance

Last but certainly not least, 13.04 sports some much-needed speed improvements in the Unity desktop. The whole Unity experience had really started to lag in recent versions, and Canonical has fixed much of that in 13.04. There's still probably some room to improve, but it's noticeably faster than it was before. That coupled with the new features makes 13.04 an upgrade worth checking out.