Tuesday morning, Boxee released its first iPad app, which lets you stream media between your TV and PC seamlessly. The app soar to #11 on the iTunes iPad Charts, surpassing Angry Birds. Today, Boxee has another big announcement, it’s adding Grooveshark’s massive music library and abilities to curate playlists, search for songs and discover new music.

Grooveshark streams 50 to 60 million songs per month to more than 5 million users worldwide. Grooveshark lets you search by artist, song, or album and you can pretty much find any song that you want. For example, I love the new song “Keep You” by Class Actress but it’s not on Spotify, it’s not on Rdio, but it is on Grooveshark, here. Grooveshark gets its content from letting users upload their own media so it usually has great remixes that can’t be found on Pandora, Spotify or Rdio.

Anyone can sign up for an app at Grooveshark.com for free. Continued access costs $9 per month and allows you to stream all the music you want on Boxee, Palm, BlackBerry and Nokia devices, and your computer.

03 MyMusic 520x291 Get down with Grooveshark, now available on your Boxee

To celebrate the launch, Boxee partnered to give away several Grooveshark premium accounts and 5 Boxee Boxes, click here to enter. The person with the most pathetic entertainment system wins!

07 Queue 520x291 Get down with Grooveshark, now available on your Boxee