Cortana reminds me of some scary cyborg from a sci-fi show. It learns what you do, where you go, who you are, who and what you know, something that no piece of technology should ever know about you (No, I do not use Facebook).
I'm going to get my WP 8.1, turn off the location services,turn off all of the Cortana tracking features (Hopefully this can be done), and enjoy 8.1. I hate to disable the best feature WP 8.1 has, but I value my privacy over a nice-looking app that talks.
The last thing I want MS to do is send my location data, people I know, etc to the government...
By the way, thanks for crashing my profits, MS... (Signature). I guess i'll have to work on a Cortana exploit to make up the loss.