Help understanding video display (iPhone 4)

[AceCoolie]

Hi everyone. I need help understanding the display when I select video on the iPod application. I've got an iPhone 4.

1. What does the blue dot mean next to Year one?
2. Why do The Simpsons and Year One not have a thumbnail?

Thanks!

 

[jrt67ss350]

Blue dot means that the video is "new" and has not been viewed yet. A half-filled blue dot means it's been partially viewed. Not sure about the thumbnails.