DENVER, USA: Internet search engines pride themselves as being neutral providers of information.

But as competition mounts to own the connection between fans and online content, tech behemoths like Microsoft and Google increasingly are turning to their search engines to help drive their entertainment content strategies.

In June, Microsoft launched a new entertainment vertical to its Bing search engine, which among other things aggregates full-track streaming from Zune, details on upcoming tours and buy links within the results for any artist, album or song search.

Google put together a similar package last year and is now building a music download service of its own that would be tied to its search engine and Android mobile operating system.

Given the high volume of entertainment-related queries that the search engines handle, it was only a matter of time before they took bold steps into the space. According to Microsoft, 10 per cent of all Internet search queries are entertainment-related, with music lyrics alone accounting for 70 per cent of those searches.

With the Bing upgrades, Microsoft is trying to position itself as a better entertainment discovery tool than Google. While both Google and Bing have links to stream full songs found in search results, Bing has the more complete package with additional details on tour dates, lyrics and buy links.

However, all that may change once Google gets its music act together. Sources confirm that later this year Google will launch a music download service that's tied to its search engine. Currently, music searches on Google link to full-song streams provided by MySpace Music, as well as Twitter feeds and other information, which it launched late last year.

Exactly what Google has planned is unclear, but a hint was given during a developers conference for the company's Android mobile platform in May. At the event, Google announced the acquisition of Simplify Media, a content-synching technology that the company demonstrated can be used to automatically synch and stream music purchased online to any Android phone containing the technology.

Whether this is an interim step toward an eventual streaming subscription service is unclear, and Billboard hasn't confirmed any additional details on this point.

Potentially interfering with both plans is an increasingly aggressive effort by the recording industry to have search engines remove links to infringing material. BPI, the trade group representing U.K. record labels, raised the stakes in June by issuing a takedown notice to Google, demanding it remove links to 17 songs from third-party websites it deems infringing, such as RapidShare and MegaUpload. Google hasn't yet responded, but its next steps will be telling.

Should Google comply, it would set a precedent that will almost certainly result in a flood of additional takedown notices from every music label and publisher eager to eliminate pirate links on the world's most popular search engine. If it refuses, there could be another court fight coming as big if not bigger than the $1 billion lawsuit Viacom brought against YouTube -- which itself is heading to appeal after Google recently won a summary judgment to dismiss the case.

As for Bing, Microsoft senior VP of online services Yusuf Mehdi assures the music industry that it will comply with any takedown requests, but has no plans to alter the search algorithm that determines search results.

"We're pretty true to the algorithmic ranking in the Web results," Mehdi says. "We're obviously not going to surface that kind of stuff in the Bing box, but the algorithm that determines relevancy of search results we'll stick with."

While Bing's moves are interesting, it's Google that has the market-moving leverage. According to the most recent data from information services firm Experian Hitwise, Google's search engine in May led the pack with 72 per cent U.S. market share, with Yahoo second (14.4 per cent) and Bing third (9.2 per cent).

But when it comes to music, all of them stand in the shadow of Apple, which still commands 70 per cent of digital music download sales in the United States, according to NPD Group. While Apple has no presence in online search (yet), both Microsoft and Google are competing with Apple on the rapidly growing mobile platform - Google with Android and Microsoft with the new Windows Series 7.

Successfully tying together a cloud-based music service with an online search and discovery system and a path to mobile phones - not to mention advertising around it all - is the digital content battlefield of the immediate future.