I'm starting to get over obsessed (if that's possible) by mobile site design. It's a small screen, people are on the move, we need to think in a different way to get the most out of the opportunity.
I found some great tips from Google on mobile website optimisation. From buttons, to content to white space.
Long and detailed but really good stuff.
Part 1: Mobile Website Optimisation - 5 Considerations when Prioritising Content.
Part 2: Mobile Website Optimisation - How Effective Use of White Space Can Improve the Mobile Website Experience.
Part 3: Mobile website optimisation - 7 considerations when designing buttons on mobile websites - Google Mobile Ads Blog.