Here are some key points to know about Google and mobile friendly websites:

• Google differentiates between traditional mobile phones and smartphones.

• Google has two bots: Googlebot and Googlebot-Mobile. Googlebot crawls desktop-browser type of webpages and content embedded in them and Googlebot-Mobile crawls mobile contents.

• Currently only traditional phones are supported with special useragent strings within Googlebot-Mobile, not smartphones (this may change).

• Google said they “expect smartphones to handle desktop experience content so there is no real need for mobile-specific effort from webmasters.

• It does not mean you can’t serve a special style sheet to smartphones, Google said, “the decision to do so should be based on how you can best serve your users.”

• URL structure: For Googlebot and Googlebot-Mobile, it does not matter what the URL structure is as long as it returns exactly what a user sees too.

• Using the same URL “is not considered cloaking by Google.”

• Mobile sitemaps: you should include only mobile content URLs in Mobile Sitemaps, even if these URLs also return non-mobile content when accessed by a non-mobile User-agent.

For more information on this please check out this great article: http://selnd.com/mobilepaidsearch    

Schwartz,Barry “Google on Designing Mobile Friendly Websites” 2/22/11.http://selnd.com/mobilepaidsearch