Pretty much all internet traffic, Gmail, web searches, websites, skype calls, iMessages, etc. are encrypted. Any website starting with https and anything with standard SSL is encrypted.
All that data, by NSA policy simply because it is encrypted, is collected and they may store it forever. For any of you smart nuts out there please let me know if it is plausible that they do retain all encrypted imformation forever, or do they not have the actual storage space to do so?
In the most likely case that they do retain all encrypted data and communications forever, Forbes says “Fail to encrypt your communications, and they’re vulnerable to any eavesdropper’s surveillance. But encrypt them, and they become legally subject to eavesdropping(and retention forever) by the most powerful surveillance agency in the world.”
An official leaked NSA document says “In the context of a cryptanalytic effort, maintenance of technical data bases requires retention of all communications that are enciphered or reasonably believed to contain secret meaning, and sufficient duration may consist of any period of time during which the encrypted material is subject to, or in use in, cryptanalysis.”