Will people stop saying x is prism proof without actually thinking about it first. Until you are self hosted(in a physically secure location), with "perfect" encryption, with clear delineations of trust, its never going to be PRISM proof.
Where are your emails destined to go? PRISM.
Where is your server hosted? in the cloud? well hello PRISM, good bye private key.
True, but this is still very much worth paying attention to, even if it's not NSA-proof today.
If we are ever going to get to a future where self-hosted solutions gain widespread adoption, it will be enabled by projects like Kolab making incremental progress towards a Google Apps-like experience.
The only way privacy-protecting technologies will ever become mainstream is to make them more usable, more beautiful, and more trendy than the PRISM-friendly alternatives.
Well there was that famous CIA statue that nobody could figure out for a while. Turns out the NSA solved it pretty fast, but they just didn't tell anybody.
And being the codemasters for the most powerful western country, I should hope that they employ people who are able to beat what people do on their free time.
http://www.kolab.org/community/upstream-communities