pageoneresults - 1:52 pm on May 7, 2012 (gmt 0)
Shouldn't We All Be Developing Sites For Responsive Design?
Yes. And, if you don't do it now, you'll be that much further behind.
Did you know that GA reports Viewport Dimensions? Go to...
Audience > Technology > Screen Resolution
Ya, they refer to it as Screen Resolution and not Viewport Dimensions. What you'll see in the top 10+ are your most common Screen Resolutions. These are folks surfing with a maximized browser. Then, as you scroll through the report, you'll notice the numbers start to change to a variety of dimensions, these are the Viewport Dimensions.
At the end of 2011, I reviewed stats for a handful of domains under my management. All of them have a 320x480 in the top 20 Screen Resolutions. Many of them have a 240x320. The smallest I've seen is 122x133 with the largest being 5760x1080. Can your site scale to fit those dimensions?
Here are the Top 10 Viewport Dimensions for mobile and tablet devices. This is from a site that averages 200k visitors per day.