Microsoft has launched its MSN search engine. The software giant's rival to Google has been in beta since November, and now boasts an index of some five billion Web pages. Bill's even done a letter for it.

"The whole goal with our new search service is to deliver answers faster to users," said Mark Kroese, an MSN general manager. "In a world where the search engine user experience is getting lots of links but no answers, we're really focused on giving users quick answers to their questions."

The new engine will let users search websites plus content from Microsoft's Encarta encyclopedia and its music service. It also features a variety of tools to let users adjust searches, such as narrowing results by language or domain, or from a specific geographical area in a feature called "search near me".

MSN Search is available in 25 country versions, including the US, UK, Spain, Sweden, India and Germany - and in 10 languages.

It still has a way to go though to take on Google, In December, Google drew 34.7 percent of US search engine users, while Yahoo came second with 31.9 percent. Microsoft was third with 16.3 percent.

The software giant promised to keep the pressure on. "We're now really poised to deliver new features on a very aggressive schedule," said Kroese. Likely areas of improvement are increasing the size of the index, broadening the types of searchable documents to include, for example, video content and maps, improving result relevance, and expanding the ability to personalise searches.