Syncing artwork between iTunes 10 and Apple TV (2nd Generation)

I just created a movie (MOV) from a slideshow in iPhoto. Everything is great, but I can't seem to apply a slide as the artwork outside of adding it later in iTunes or assigning it through iMovie.

When I add it through iTunes later, the artwork won't sync with Apple TV. Any ideas?

As well, does anyone know what exactly the icon Computer/Apple TV does on the system tray on iTunes 10?


Thanks,
Barry