Google's subscription-based music service will take shape at tomorrow's I/O conference in San Francisco. According to The Verge, the search giant has signed licensing deals with Universal Music Group and Sony Music Entertainment for YouTube and Google Play. The latest rumors, from Fortune, suggested the service would utilize both YouTube and Google Play, corroborating today's report. Sony, incidentally, has reportedly held off signing with Apple (thus far) for its fabled iRadio service.

If a Google music service is imminent, it would allegedly mirror Spotify's model, which offers on-demand streaming. The service would then presumably tie-in with Google Play, allowing users to purchase songs at will. Google's licensing agreements with Universal and Sony would come in addition to an earlier agreement with Warner Music Group, according to Fortune's previous report.

The arrival of Google's streaming service would preempt Apple's service, which is rumored to take a Pandora-like approach, and let users buy music through iTunes. We'll find out in less than 24 hours how Google plans to leverage the service alongside YouTube and Google Play. Google Play itself is still a young platform, but YouTube is an immense property that currently garners 800 million unique visitors each month. That's a lot of potential ears to reach.