A few nuggets from a launch-day interview with Scott Erickson, a Zune senior product manager working with advertising and marketing, as well as other aspects.

Deals with the labels: Erickson confirmed that Universal Music Group is the only record company with a device royalty. “Right now that deal is just with Universal ... We’re definitely in talks with other labels.”

Sharing limits could change:  Erickson said the three plays in three days limit is subject to change. It could be five plays in five days or some other mix. “I think for music it is a balancing act,” he explained. When I asked about the built-in damper on viral music—a shared song cannot be passed along—he said the one person limit was meant as protection against piracy but that stricture could change as well. I’m less certain that Microsoft would be open to lifting the inability to share non-DRM protected music. Zune actually prevents sharing of any audio file, which sounds like a hack challenge if I’ve ever heard one; although images can be shared multiple times. Erickson added, “I think you’ll see a lot of different types of ‘sharing.’” (Microsoft CEO Steve Ballmer told Bloomberg Zune will add video sharing, probably for user-gen material, and eventually a combo phone model.)

Launch date: I was amused to learn that one piece of marketing strategy I was planning to give the team credit for was actually happenstance—the Zune’s launch on the same day of the week—Tuesday—new CDs and other media usually appear. Erickson said it “definitely was not an overt thing we did. ... It was the day that worked best for us.” (Update: It’ was also the date of Microsoft’s annual meeting.)

Brown Zune: Picking controversial brown, more of a fashion shade than a CE favorite, as the third color was meant to be a conversation starter. Erickson: “We want people to say, ‘Wow – I hate that or this is incredible, I actually love this.’”

Emphasis on music: While reviewers and critics complain about the lack of a video store in the Zune Marketplace and other decisions that might make the Zune more appealing as an overall device, Erickson and others at Microsoft are firm that the initial focus ha to be on music. They’re exploring a video store—I fully expect one when they need the next boost—but Erickson said that wasn;t as important to users looking for a music experience. Ditto with full wireless use.

Cultural core: One thing is clear: Microsoft has bet the whole pot on reaching music’s equivalent of the gaming core that made Xbox a success. The focus for the launch period is on getting the name out there and building a brand. “We want people to say you guys are credible in this space, you are about music.” Hence the multiple launch parties in music venues matched to various genres. Erickson says they call it a “cultural core,” explaining, “We’re talking to them first and then mass market will continue to follow.”