We took a whack at this problem (agree it is big issue worth solving) last year with Streamliner, http://www.streamliner.co.

(Hint: ignore the video-specific text and paste in a blog post or article URL.)

Couple of examples: http://www.streamliner.co/s/S2C72QTZ/booster-camera-video-of... (video) and http://www.streamliner.co/r/eErbi/always-be-skeptical-of-nut... (text)

We rolled out with video initially because of text-stripping issues and the extreme low likelihood of users installing a bookmarklet/extension. Building a community of engaged trustworthy summarizers is also very hard.

Good luck!