To the casual observer, the ongoing quest by SanDisk, Creative, and Microsoft's Zune to dent the dominance of Apple's iPod is of the Sisyphean variety.

But although the iPod and iPhone continue to own the portable digital media space, SanDisk and Creative have each periodically unveiled competitive products that they hope will register with consumers, and Microsoft did the same today.

Nearly one year after the much-hyped debut of the Zune player and digital store, Microsoft unveiled three new Zune players. Two of the players are flash-based, coming in 4GB ($149) and 8GB ($199), whereas the other offers a major upgrade on the original Zune, going from 30GB to 80GB but retaining the same $249 price tag.

The flash models will come in pink, green, black and red, and the hard-drive version is in black, an indication that the Zune's much-discussed brown flavor will be eliminated. Microsoft said it has sold about 1.2 million Zunes to date.

Microsoft said the new players, which will hit stores next month, will come with wireless syncing via Wi-Fi from PC to Zune, meaning that users can more easily sync their music collections between their PC and their Zune via Wi-Fi.

Zune will also reduce restrictions on the ability of Zune users to share songs via Wi-Fi, a feature that Microsoft touted as unique when it launched. Instead of only sharing snippets of songs, users can now share full-length songs, but there will still be a three-listen limit before the recipient is prompted to buy the song.

However, the new Zune will not come with the ability to buy songs wirelessly, a feature that Apple added with its iPhone and iPod Touch last month. J Allard, the Microsoft corporate VP overseeing Zune, told Reuters that the delay was due to concerns with dealing with spotty Wi-Fi, but said, "We'll get it though. It's just a matter of when."

The Zune Marketplace, Microsoft's answer to iTunes, made two major upgrades. First, more than 1 million DRM-free songs have been added to the catalog. Secondly, users will be able to automatically import TV shows recorded to Microsoft's Windows Media Center.

Finally, Zune will be launching a social networking site, dubbed Zune Social, later this year.

Allard told Reuters that Microsoft isn't as concerned with its distant second in the race for market share as it is about putting out a good product.

"The market-share thing is the easy thing to discuss and write about, but it's such a bad measure," Allard said. "Talk to me in six or seven years about market share. Talk to me this year about the experience we are creating."