Update: see our complete review and our later take on the new ads that roll as certain apps launch.

The Zune HD goes on sale today, and the firmware for the new device should be available by the time you read this (initial devices were shipped without the needed firmware, making them all but useless until hooked up to a PC). Hopes that Microsoft might offer support for the Mac or for Linux machines didn't pan out (and were always a long shot), but the Zune does have a few slick tricks up its sleeve. Let's run them down in preparation for our full review later today:

3.3 inch OLED screen: Sure, we knew all about it, but how does it look? With a unit in our grubby little hands, we can confidently say it looks pretty damn good. Colors are saturated and the screen is terrifically bright—so much so that even my dad (!) commented on it after seeing the device begin playing its demo movie. Resolution is 480 by 272, and the Zune HD features an accelerometer this time in order to do automatic screen rotation. The screen is driven by NVIDIA's high-def, low power Tegra chip.

Apps: Yes, apps are coming to the Zune, but in a limited way. Here's how Microsoft puts it: "Simply go to the apps catalog and select the ones you want and sync them to the device. Zune apps are free. We are introducing a handful of new and updated casual games, along with a select group of utility apps, such as weather and calculator. These first apps for Zune HD are an introduction of what will be an ever growing library."

Sounds neat, and should add a good bit of utility to the device, especially if Microsoft rolls out a competent e-mail reader (a Web browser is built into the operating system). But it's also clear there will be no third-party app ecosystem—probably a wise choice, given Microsoft's small market share here and the wide range of competing smartphone platforms and portable game devices, each with their own app stores and developer ecosystems.

Size: The Zune HD is much smaller than expected from pictures—significantly smaller than either an iPhone or an earlier hard-drive Zunes. In fact, it's half the depth of the earlier hard-drive Zunes. It's larger than the iPod nano and the earlier Zune flash units. Two models are available, 16GB and 32GB flash units, in five colors.

Rich artist information: Zune HD will automatically grab album art but also extra material like biographies and related artist information when synced to a PC, even if the songs came from somewhere besides the Zune music store. This information will be viewable on the device while playing back media.

Codec support: All the bases are covered here. The Zune HD can handle WMA, AAC, and MP3 audio along with H.264, MPEG-4, and WMV video, along with (hugely) limited support for DVR-MS files from the company's own Windows Media Center DVR. When provided with the right connectors (sold separately), it can output some HD video over HDMI.

Wireless: Still present, and the Zune HD is still capable of syncing its media wirelessly with a PC. Like Zunes before it, the Zune HD can also stream music directly from the Zune music store for those with an unlimited monthly music pass. 802.11b/g are supported, but not 802.11n.

"Hello from Seattle": Yup. It's written on the left side of the device in tiny, totally lowercase gray text.

The headphone jack: It's on the bottom.

We'll be bringing you our complete Zune review later this evening. If you have any questions you'd like answered, leave a comment and we'll do our best to oblige.