There should, but I just can’t remember just now. BUT ALSO, keep in mind that Amazon is selling their own little box for the TV ... SO ... they may want to restrict it just to their own device. I can’t say for sure, though.
The way I see it, and coming from the perspective of someone who has Roku, is that the way that they would jip you would likely be the other way around, chances are that the Amazon box won’t have an iTunes channel. I am going to take a wild guess at that based on the fact that the Roku I have does not support iTunes, there is a freeware converter that allows you to get your iTunes media and music on to format with your google library, but not including iTunes is how I would be willing to bet that they would give the sucker punch to their competition. I am pushing and campaigning with my wife to make our next box an Apple TV though, because it’s worth the extra 25 bucks.