At this point, it's clear that Microsoft plans to expand its Zune initiative beyond the current music device, software and service. The question is how. With the Zune Phone rumors fading into the background, for now, the focus has turned to the company's plans to expand Zune capabilities to Windows Mobile devices, a strategy that Microsoft CEO Steve Ballmer acknowledged this fall.

But beyond those comments, the company has been quiet about its plans. Unless you look at its job listings.

"Zune Services is building an entertainment store for a wide range of Zune clients or 'tuners,' " reads a Dec. 2 posting for a Web services development job. "Today these tuners include the Windows PC client, the Zune web site and the Zune device; in the future there will be more. Each of these tuners access a set of rich web services implemented by Zune and soon by Musiwave as well."

Musiwave is the Paris-based mobile music and entertainment services provider that Microsoft struck an agreement to acquire last year. Mobile operators such as Orange, Vodafone and T-Mobile use Musiwave for ringtones, music and other content. At the time of the announcement, Microsoft said it would use the Musiwave technology to help various elements of its "connected entertainment" strategy.

The job postings, published to Microsoft's careers page in the past few weeks, give new clues about the Zune expansion and suggest a significant Musiwave role. Some also convey a sense of urgency.

"The Zune organization is making a strategic change from a 3rd party content provider to in-house," reads a Dec. 2 posting for a software development job in Microsoft's Musiwave subsidiary. "We need to rebuild, re-architect, and revitalize a content ingestion pipeline that powers the entire Zune business. And we have a very short time to do it."

"We’re building a team in Redmond to help power Zune Marketplace," reads another listing. "This job would work towards the overall strategy and collaborate closely with the Zune Redmond team and the Musiwave Paris team."

A blurb from another listing: "As Musiwave powers Zune Marketplace, we’ll need to 'ingest' data from multiple sources and process it in a way that’s optimal for Zune to show to the users. We’ll also continue to look at new types of data we can load into our system and expose to make music in Zune an ever richer experience."

And another: "For the record labels, Music is a business and in order to let consumers enjoy music in new and interesting ways, Zune has to license music from the labels implement certain controls. To enable new experiences with Music, we’re hiring a developer to understand these requirements and implement them for Zune’s music offering."

It's interesting stuff, and a sneak peak of what we're likely to see from the company at some point in the coming months.

But the underlying question remains: Even expanded to Windows Mobile phones, will the Zune initiative have what it takes to become a more credible rival to Apple's iPod, iPhone and the iTunes store?