Duane Forrester from Microsoft posted on the Bing Search Blog a significant statement on mobile SEO. He said that Bing proposes the “one URL per content item” strategy.

Google has not been bold enough to make such a clear proposal, but Bing has and I am happy they have done so.

Bing said:

Bing explained the benefits include:

You have more ranking signals coming to this URL. Example: the vast majority of mobile URLs do not have inbound links from other websites as people do not link to mobiles URLs like they link to regular web-situated URLs.
This is also less search engine crawler traffic coming to your web servers, which is especially useful for large websites. Fewer URLs to crawl reduces the bandwidth our crawlers consume.
Less work (and potentially less cost) building, updating and maintaining a stand-alone mobile-focused website.

At the same time, Bing is not suggesting that every single mobile URL should match to a desktop URL and be that desktop URL. There are times when you need to have mobile specific landing pages, but when you do, Bing suggests that you “opt to block from us via the usual methods (robots.txt, webmaster tools).”

Google on the other hand has been very indecisive on their mobile SEO recommendations. The latest recommendation from an individual Googler but not as an official Google policy was to use the one URL approach but Google has suggested so many different methods in the past.

I am very happy Bing has taken a stance on which way SEOs and webmasters should focus and try to set some guidelines for mobile development in the future.

Forum discussion at Bing Community.