1) mass media is becoming (or really, already) the internet now rather than just Evening news/newspapers and Time magazine.
2) yes they've amped up the change but I believe only in vocab and really only in adding vocab (I don't think other vocab is falling away or being replaced)
3) All your points about specific grammar or whatever changes are all happening and important, but it is my semi-educated opinion that those changes will not be enough to alter te language significantly (I think they will act like temporary slang than new permanent changes)