As part of today's Google I/O keynote, Google debuted its upgraded Music product. Under the Google Play naming scheme, Google Play Music All Access provides unlimited streaming via the web and up to 10 authorized devices for just $9.99 per month, the same fee as charged by Spotify. Better yet, if you sign up for the free 30-day trial before June 7, the monthly charge will be just $7.99.
As you can see above, I've already signed up for the service. It's important to note that the service is only currently available in the United States. I've also been unable to get All Access working on my iPhone via Google's web app. In order to compete directly with Spotify, Google will need to develop a desktop app and an iOS app.