Hmmm...my feeling was that if it were so obvious to Roku users that "UP" = "Back", then Roku would not have included a separate Back button on the Roku 2 remote.
There's Back, Up, and Home - all could conceivably cause the same thing to happen - to exit the channel. It's anyone's guess why they include redundant buttons to specifically cause confusion as to how their device works, but it's the way they want it.
Dos anyone have the new remote with a dedicated netflix and hulu and crackle buttons? Do those exit the existing channel when pressed too?
No offense intended - but do we really need 6 buttons to press to exit a channel? It might give the impression that watching content isn't what the box is about - it's more about stopping content? Only OK works by default to select something - while you can make Play select something too with extra code.