* This past Tuesday, Wolfram Alpha announces its structured data search product. On the same day, Google announced its new structured data product.
* July 28, 2008, so called Google killer Cuil launched its search engine. It claimed that their index of 120B documents was 3x that of any search engine. Three days before though, Google announced it knew of 1 trillion URL's.
* June 3, 2008, Wikia Search launched a feature that allows users to add and delete URL's to search results. July 16, 2008, Google announced that it is bucket testing similar features. The features went live a few months later.
* February 25, 2009, Cuil announced it is integrating longer snippets into its results. March 24, 2009, Google announced...you guessed it....longer snippets.
and finally closes his argument with ....
I guess the fact that there are zero switching costs for search engines makes their paranoia run a bit higher than most.....
...provoking Matt Cutts to react with the "facts".
Once instance where I have seen Google drawing from others ideas is with Live Search's "Show Similar Images" feature.
Also see:
Search Engines in the post-Google era
Google Search - Then & Now