Exec summary: This is not caching. It is reduced latency for your visitors by removing connection setup over a large geographical distance. It also reduces the latency your web server has to deal with to effectively zero, but you can do that with Nginx. It also will reduce your bandwidth consumption from your providers perspective to a fraction of what it was. I think describing this as caching hides the real benefit…
Nothing new, this is all just repackaging. This is all just basic CDN proxy tech all providers (including CF) had for years.
Giving it a cool name, dose not make it new or exiting.
Here are some helpful links - CF customer testimonies:
http://x-pose.org/2012/02/speed-up-your-site-disable-cloudfl...
http://www.husdal.com/2011/07/01/incapsula-versus-cloudflare...