I did the original study at Google on SPDY over mobile networks, which was a small-scale lab study. Since then, we have collected data from millions of Chrome Mobile users which shows that SPDY does tend to outperform HTTP on cellular, but of course there are many factors involved - the content of the site, the network conditions, etc. I haven't had a chance to get this data into a form that can be shared, which I really need to do. Still, the authors of this CoNext paper did a really nice study. I hope we have more to share on this in the future.