Interesting suggestion, although it has nothing to do with the Roku Stick. Your Premiere is not a stick, although the latest ones look similar, don't they? :D
The problem I envision with this is that it would have to be part of the Roku OS itself. It wouldn't be much use if it were only stored within the channel itself, and you can't recall which channel it was in the first place. The next problem is how to implement it. The Roku remote has a limited number of buttons, and some of the buttons are taken over by the channel while in use.
How would one mark a video to be added to the bookmark list? In many/most channels, every button already has a function. And this function would have to work on all currently used remotes. So you couldn't use a button, such as mute, because not all remotes have that button.
Not to put down Roku users, but programming a button for a long press is simply going to confuse a lot of users. Roku remotes are designed for simplicity, and ease of use.
As I said, an interesting idea. Just having trouble getting my mind wrapped around the how. And I didn't even touch how limited memory space is on a Roku. But good programmers can do amazing things.
