Eventually (well...now?) they'll be able to run cyphers through our communications to look for obvious signs of "terrorism" and whatnot. Voice recognition is the future (well maybe now, but it's surely only so efficient) as it will be a part of more complex AI. This voice recognition will surely be used to the advantage of people who are looking out for "our best interests". Well, even visual pattern recognition, perhaps, but away with that for now. (Interesting that it said they'll keep textual communication for 30 days but aural for 60)
Let's say I'm talking with Person A on Skype about making bombs, and then go on my way. A week later I blow up some stuff and maim some passersby, and the police get wind of my having to do with it and have ample evidence to get a warrant or whatever they need to look at my goods. They'll contact Skype or whomever, and ask for all my logged video/audio transmissions. They'll use this as a means of finding out about what they need to find out about and hopefully stop it from happening in the future, which is good.
The important question is are they going to constantly run cyphers through everyone's communications no matter who you are, as to find a string of data that corresponds with some "bad thing" (I don't mean to start an argument about what is right and wrong, just giving examples of what the government will probably look for): smoking weed, doing acid, raping women, teachers masterbating in kindergarden classrooms, clubbing seals and tearing them apart just to throw their body parts from tall buildings to watch them splat. Then one would think one's freedom is severely limited, because what if, as I just did, said these things in jest? Then you'll eavesdrop on me and listen to all my secrets that I only want to tell my special friend about, heh?
I don't know, a debate would kind of be intriguing...
P.S.: I don't know much about Skype, and assume you can video chat as well.