Google Play won’t allow you to directly import your Music CDs. However, iTunes let you. You can use iTunes to import your Music CDs into your iTunes library and then use Google Music Manager to upload iTunes library songs to the Google Music. There is even an option to upload all future songs from iTunes to your Google Music.
What are the advantages? You are using Google and if you are an Android user, you can not have iTunes on your Android to listen to your songs. Also, you won’t need to pay 24.99 for your songs to be hosted on a Cloud (i.e. iCloud).