Could Microsoft’s PMP also-ran Zune be ready for another go at the iPod? Apparently, according to Engadget, who today leaked supposed marketing materials for the new Zune HD supplied by an anonymous tipster.

While no specs or details other than a few stylized photos were released (above, courtesy of Engadget), this comes hot on the heels of rumors that new Zune hardware would be available this year.

Zune team member Brian Seitz confirmed as much when he announced via Twitter, “new zune hardware this year.”

While a new Zune is not surprising, the once-heralded iPod killer has seen better days. Microsoft, has witnessed Zune revenues plummet in recent months, dropping by more than half during the fourth quarter of 2008 compared to last year, according to an SEC filing. Also, 30GB models were plagued with lock ups and frozen screens, apparently because they were not programmed to handle the leap year.

The dedicated fans at ZuneLuv.com just registered the domain ZuneHD.com, suggesting that Microsoft has no plans for a Zune HD, or the folks at Redmond completely dropped the ball with domain registration.

Update: The folks at Technolgizer have confirmed via an unnamed source that the rumors are true and Microsoft is set to release the Zune HD in the fall. Also, the new Zune will be smaller than the iPod touch, will have touchscreen functionality, and the click wheel will be replaced by a single button.