Nobody's mentioned this yet: this solves the copyright problem that is looming over the search industry.
Beyond the very basic issue of implied consent and "opt-out" which is counter to a copyright system of copyright laws that is strictly "opt-in"...
...IMO, all the search engines are teetering on the edge of legality, in a number of ways, but particularly when they pick-out details from a site and reformat them.
Yahoo is moving toward doing this with the website owners consent.
This is a positive move for everybody.
Presumably, in more visitors.