Now you can submit your own videos to be shortened to any desired length using the HighlightCam video summarization infrastructure.  Details here:

HighlightCam API at Google Code

You can see a great example of the API applied to a nature documentary in this writeup over at VentureBeat:

Automatically cut videos down to the best parts: HighlightCam releases API

and a technical discussion at Hacker News.

For now you can submit up to 20 videos a day for free!  A paid version for heavy users is coming soon.