has anyone used the new apple tv unit

Yes, sir....and it's a wonderful device. Sounds great and is super easy to setup and use. If you are an iTunes user and don't need 24/96 compatibility, I highly recommend it. There are some other AG threads about the new ATV that you should search for to get a better perspective.

Can someone explain how the ATV works? Do you attach it to a HD? Do you need a monitor for it? Thanks, Peter

@Peter: It requires a HDMI display to setup, and is more functional with a display when using it. If you just want audio streaming from iTunes, the AirPort Express is the best choice. When used with the Apple iOS Remote app, it allows you to control and access your iTunes libraries.

I don't really get it. You need to hook the ATV up to a computer. Most folks hook the ATV up to an external DAC for best quality sound. If you have an apple computer with optical out, why not just hook that up to a high quality external DAC? I guess otherwise it may be worth it - does tha ATV serve as a USB, LAN or wireless converter from your computer to a DAC? Or is the appeal that you get to use it for video too, so you are controlling your whole entertainment experience? How does it interface with a PC rather than a Mac?