If only, but I just don't see companies like Google, Microsoft or Facebook implementing end-to-end encryption like OTR, ZRTP and PGP for their services, and even if they do, I'm not even sure I'd trust them not to implement a backdoor to get that data before it's encrypted somehow, at the behest of the government.

Unfortunately, the alternatives will have to come from elsewhere - from disruptive (in privacy) start-ups that will launch only services with security in mind from day one, as they try to steal customers away from those companies.