I’ve been checking it out and it looks quite cool, though basically it is only an Airport Extreme with the hard drive inside it, so no AirTunes etc. But full Airport Disk support, so it can be used for storage or time machine backups for a number of machines, and you can add another disk (and/or a printer) via the USB port.
What I’d really like to know is how quiet is that hard drive? If it’s near enough silent, I might go for it just for that.