Google has posted a pair of webinars from its "GoMo" campaign, which is an initiative to get people to create mobile-friendly sites. One of the webinars is for advertisers and one is for publishers. They both include tips and case studies on sites that have gone mobile.
Frankly, you shouldn't need Google to tell you that you need to be optimized for mobile these days, but there is still plenty to be learned.
In the first one (the one for advertisers), Google discusses mobilizing your site, maximizing mobile ads, and tracking/measuring them. The second one discusses why you should go mobile, provides tips for building a mobile site, talks about best practices and explains how to get started.
As a bonus, Google has also made the slides from the webinars available to download here (pdf).