A great feature in OS X Mountain Lion - is system-wide audio streaming over AirPlay. This feature has been available on iOS devices for a quite a while, but was confined to iTunes on Mac OS X Lion and earlier.
With Mountain Lion you can AirPlay directly from all applications on your Mac to your Libratone AirPlay speaker.
In System Preferences choose Sound and Output - and select your Libratone speaker for sound output. All sound from your Mac will now be sent directly to your Libratone speaker.
Please note that AirPlaying to multiple speakers simultaneously still requires iTunes.
AirPlay for video sound (movies, youtube) is not recommended due to sync issue between video and sound. Relates to AirPlay and not to Libratone. All AirPlay speakers on the market will experience the same issue. For video sound - use a mini jack cable between computer and speaker.