Ahhh, sorry! It's not as intuitively as I wish it was. I've been struggling with how to keep the design simple and still allow the proper back/forward functionality. I think I know what you're getting at with the grooveshark/youtube playlist. Do you mean how you see the thumbnails along the bottom and nothing ever disappears but rather shifts left and right? I'll definitely look into making it like that if I can.

Yeah, and just have a way to make favourites and rank (1/10). You could also have stackoverflow-like sub comments (that can be hidden.)

Also, is there a way of displaying how many highlights a quote has received, and from whom/when?

I do have the number of highlights. I'll consider showing those in the next release.