Now, we've gotten confirmation that the rumors are true and data don't lie. Google is, indeed, rolling out a new music search. This update will roll out over the next day to all U.S. users.
Why the focus on music? Google says two out of the top ten searches in the U.S., according to Insights for Search.
When you get the update, you'll be able to sample music directly in the search results. Google is partnering with MySpace (which owns iLike) and Lala to provide the samples. You can search via artist, song title or even small parts of lyrics you remember.
Google is also partnering with Pandora, imeem and Rhapsody. You'll see links to these sites where you can discover new music.
Here's a screenshot per the Official Google Blog: