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".
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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."