I saw this demonstrated today and it looks good. I like the way Ancestry.com implemented it. The following announcement was written by Ancestry.com (click on any image to see a larger picture):
Last October we launched Ancestry Labs to test a few new ideas, and we’d like to thank all those members who contributed a lot of great feedback and discussion around these. Today we’re excited to announce the introduction of one of the ideas, Web Search, into the main Ancestry.com search.
Why are we launching Web Search?
We’ve heard from many members that although Ancestry.com has the broadest collections of historical records available, it certainly isn’t completely comprehensive. Every day, digital records are being published on sites across the web, many of which are free to access.
These sites can be a great resource in helping break through brick walls, however, it can be hard to know where to find sites that are relevant to your ancestors, and it also takes time to work out the best way to search them once you do manage to track them down.