The surprising news of this week is the claim by Google that Microsoft has been 'cheating' by taking search results from Google to use on their Bing search engine. The story was first broken on Search Engine Land and has quickly developed into a war of words between the two leading search engines.

The articles reports that Google has recently run a sting operation against Bing that, it says, proves the Microsoft search engine has been watching what people search for on Google and the sites they select from Google’s results. They have then used that information to improve Bing’s own search listings.

Bing doesn’t deny this and say that use 'multiple signals and approaches' which seems to include tracking search activity through the Internet Explorer browser and the Bing toolbar. They accuse Google of manipulating their search results to identify one element of Bing's search criteria, and to time the exposure of the news to coincide with a Microsoft event to discuss the future of search.

This story is already generating much news and blog comment and is likely to run for some time as the two search giants exchange claims and counter-claims.