Search for an artist, an album name or even some lyrics and Google returns a list of songs that can be played with one click. Full music previews are provided by iLike and Lala, but Google also links to other music sites: Pandora, Rhapsody and imeem. When you click on a music result, Google opens a player in a pop-up window, which isn't very user-friendly.
"With Lala, you can hear one full length preview per song. Each subsequent play will be a 0:30 clip," explains Lala. This limitation is very easy to bypass: just clear the cookies for lala.com.
The OneBox is limited to the US, probably because the music sites that partnered with Google can provide full previews only in the US. I didn't manage to trigger the OneBox, not even using a US proxy. The sample searches provided by Google include some additional parameters that need to be added to a Google URL:
http://www.google.com/search?hl=en&q=Bob+Dylan&esrch=MusicOneboxDemoOptin::LaunchDemoOptIn
Google says it will be "rolling this feature out gradually to users across the U.S. over the next day".
Not wanting to feel left out, Yahoo reminds users that it launched a similar feature last year. "Since launching a partnership with Rhapsody in September 2008 and launching the FoxyPlayer last year, music has been an integral part of the Yahoo! Search experience as well. We have found that nearly 6 percent of all Yahoo! searches are music-related."