I've been using the Apple TV since October 2010 after my pre-order arrived. I should note I live in the UK and use the UK iTunes store so the content selection is slightly different to US consumers.

It looks cool next to the Xbox and PS3. The UI isn't amazing, it's better than most TVs or other TV boxes, however, it's not as good as the PS3 or Xbox. It's fast at doing what it does and is only limited by the UI and Internet connection. The aluminium remote looks good with limited functionality, about the same as any other remote really. However, the remote app is amazing and AirPlay which is the main thing I use this for is really good.

To conclude: It's a good £99 accessory from Apple.