The Google Music service that's become the worst-kept secret in the music industry may not be live yet, nor is it showing signs of launching anytime soon, but we are slowly getting clarity into who at Google is building the service.

On Friday, Billboard magazine published a list of key executives involved at both the leadership and foot-soldier levels. Since then, additional sources have come out of the woodwork to help define the picture further. Here's what we know now:

Andy Rubin, Google VP of engineering, runs all things Android at Google, and last year assumed control of the developing music service. The music buck stops with him. Label sources confirm Rubin has personally pitched them on the plans for Google Music. It's unclear whether he'll continue to run the service once it launches, or if the company will hire an outsider with digital music experience. The executive search for such a person that began last summer has stalled in favor of focusing on building and launching the service first, and source say there's an internal debate over whether an outsider or insider could best fill the role.

Reporting into Rubin are two groups: one charged with creating the music service and store, and the other responsible for getting all the label and publisher deals required for content.

Jamie Rosenberg, director of product management for Android, is in charge of the overall Android app store. Those reporting to him include Paul Joyce, senior product manager, who is taking the lead on building the music portion of the Android store. Joyce was the founder and VP of marketing at Simplify Media, the company Google bought last year as the foundation of its music service plans. Also reporting to Rosenberg is Doug Lucas, partnerships director at Google UK, who is leading the international version of the music product. Lucas joined Google in 2007 from label EMI music, where he was VP of digital business development. Finally there's Tim Quirk, head of global content programming for Android. Quirk is the former VP of music programming at Rhapsody and general manager and VP of music content and programming for RealNetworks before the spinoff.

On the business development end, there's Zahavah Levine, general counsel and VP of business affairs (although she was passing cards around at MIDEM that read "director of content partnerships for Android"). She is the point person leading all licensing negotiations with the music industry for the Google Music store and locker service. She formerly was the chief lawyer for YouTube, but has since taken on a business affairs role, and has a reputation as a very tough negotiator. (One source defined her as a "pitbull" and meant it as a term of respect.) She hails from digital music service Rhapsody, where she was associate general counsel and director of music licensing, which she joined when RealNetworks acquired Listen.com.

Reporting to her are Android business development manager Ted Kartzman, head of international music licensing for Android Sami Valkonen, and content partner manager Gwen Shen. Kartzman leads the licensing process with the independent label community, something he did while at Rhapsody as director of independent label business. He joins Google from IODA, where he was VP of client services. Valkonen leads the international licensing process among publishers in a role that's almost exactly what he did for his previous employer, Nokia, for it's now-defunct Comes With Music service. Shen's job is to manage relationships with content partners -- read: labels -- contributing to the Android store and presumably the music service. She joined Google just this January from Universal Music Group, where she was an account director and business development manager since 2001.

According to one source, Google is still looking to hire someone to take on additional major label licensing duties as well.

Senior corporate counsel Kevin Montler leads the legal end of Google's music related business, including both YouTube and the in-development service. Reporting to him is corporate counsel Elizabeth Moody, who joined Google last year from the law firm Davis Shapiro, where she helped negotiate the label deals for such digital music services as MOG, Myspace Music and imeem, among others.

YouTube remains a separate unit at Google, led by engineering VP Salar Kamangar, Google ninth-ever employee, who championed the company's acquisition. The YouTube product team comprises of head of product Dan Clancy (who was the man behind the Google Book project), and product manager for YouTube Music Chris LaRosa. The business development team is led by Chris Maxcy, VP of business development, who is supported by Ali Rivera (music partnerships and business development), Glenn Brown (head of music partnerships for YouTube), Theo Luke (partner manager for YouTube in the UK) and Je Carr (strategic partner development).