We've known for a while now that search engines like Google take Website Load Speed into consideration when displaying search results. They've even openly discussed the topic in various videos and blog posts.
Hobo recently published an excellent article that broke down the effect of Page Load Speed in detail, along with real-world cases and a list of remedies any webmaster can employ to enhance the same.
Besides just factoring into Google's search algorithm, Page Load Speed also has a higher than expected impact on a visitor's experience as well as the likelihood of them browsing multiple pages on your website before leaving.
At General Data, we've worked hard over the years to understand how Site Load Speed can be reduced, and realize the importance of shaving off time, even if its measured in milliseconds. We've come a long way in our capabilities on the same and are proud our works rank well in Google's PageSpeed Insights.