The above information does not need to feature on every page, more on a clearly accessible page. However – with Google Quality Raters rating web pages on quality based on Expertise, Authority and Trust (see my recent making high-quality websites post) – ANY signal you can send to an algorithm or human reviewer’s eyes that you are a legitimate business is probably a sensible move at this time (if you have nothing to hide, of course).
To avoid undesirable content in the search indexes, webmasters can instruct spiders not to crawl certain files or directories through the standard robots.txt file in the root directory of the domain. Additionally, a page can be explicitly excluded from a search engine's database by using a meta tag specific to robots (usually ). When a search engine visits a site, the robots.txt located in the root directory is the first file crawled. The robots.txt file is then parsed and will instruct the robot as to which pages are not to be crawled. As a search engine crawler may keep a cached copy of this file, it may on occasion crawl pages a webmaster does not wish crawled. Pages typically prevented from being crawled include login specific pages such as shopping carts and user-specific content such as search results from internal searches. In March 2007, Google warned webmasters that they should prevent indexing of internal search results because those pages are considered search spam.
Websites that have extremely negative or malicious reputations. Also use the Lowest rating for violations of the Google Webmaster Quality Guidelines. Finally, Lowest+ may be used both for pages with many low-quality characteristics and for pages whose lack of a single Page Quality characteristic makes you question the true purpose of the page. Important: Negative reputation is sufficient reason to give a page a Low quality rating. Evidence of truly malicious or fraudulent behavior warrants the Lowest rating.
Over the past few days or so, I have been seeing chatter both at WebmasterWorld and Black Hat World around ranking and traffic changes related to Google organic search. I got to say, I doubt Google pushed anything specific this week or even next week. Rankings do change by itself and new content is always being added to the index but an algorithm update - I doubt it.