If you think that the new Windows Phone 7 smartphone platform will only feature Microsoft’s Zune digital music service, think again.

During a lunch meeting, PR manager Brian Seitz showed off a model of the upcoming phone that featured a number of different music services. They included the personalized Internet radio application Slacker, Clear Channel Radio’s iheartradio Internet radio app, and a lyrics app from MusiXMatch.

All will be available on the device when it ships to retail. No new details on when that may be yet, but we’re expecting an announcement early next week with more information.

While none of the music apps demoed were music service apps (the caveat being that Slacker has an on-demand streaming service tier that would compete with Zune’s music subscription service), Seitz made assurances that no music app competing with Zune would be denied access to the device.

That said, Zune will certainly be the featured music brand, just like iTunes is on the iPhone. While other music services will need to be downloaded and launched, Zune is front and center at launch. It’s also connected through to other Microsoft platforms, such as the Xbox Live network, allowing Zune users on the phone and Zune users in front of their console to “see” each other and share tunes.

Overall, first impressions match that of earlier reports in that the device is very slick, highly graphical user interface, and a navigation that seems easy-to-use. Particularly interesting is that the home screen surfaces important information such as text and/or voice messages pending review, or the album art of the last song played, or select friend’s status updates.