And why not? Members of the social-networking Web site owned by Rupert Murdoch’s News Corporation make up a target audience record labels dream of. They buy merch, they buy concert tickets and they love music. They spread the word on their favorite artists and bands faster than any publicist can mass e-mail a press release. They’re first on indie acts, first on trends and first on what’s hot and what’s not.

And now MySpace has its own music service. Appropriately called MySpace Music, the online service is about more than just selling song downloads. MySpace Music represents a concerted effort to monetize every major music aspect of the MySpace environment.

Backed by three of the four major labels (evidently EMI isn’t on board yet) – Warner Music Group, Universal Music Group and Sony BMG – MySpace music focuses on three primary areas: the MySpace Music home page, the site’s 5 million artist profile pages and the individual user profiles.

MySpace Music offerings include DRM-free downloads and ad-supported audio and video streaming. The new music service also boasts a mobile storefront powered by News Corporation’s Jamba mobile company.

But that’s just brushing the surface. With nearly 30 million unique monthly visitors, MySpace represents more music-oriented revenue opportunities than Keith Richards has wrinkles. Furthermore, its launch immediately puts it on the same playing field as iTunes, Real Networks, Amazon MP3 and Napster. That means serious competition for the existing big boys now. Not days, months or years in the future.

“Today represents the beginning of a new chapter in the story of modern music – we’re proud to announce the marriage of the world’s biggest collection of music content to the world’s most popular music community,” MySpace CEO and co-founder Chris DeWolfe said. “Millions of die hard music fans and artists already call MySpace Music home – by partnering with these industry leaders, our vision for MySpace Music as the definitive platform for unlimited artistic expression and unrestricted user experience is finally being realized.”