I figured out how to turn off the automatic 3 blinks on the turn signal.
The blind spot thing works at weird times. I had a rental car a few weeks back, and I would be in one of two left turn lanes, turn on my left blinker, and get an audible warning. Yes, yes, car, I know that there are people to my left turning as well, now shut the hell up!
Lane warnings may be useful...but I still find them annoying. I admit I will change lanes without a blinker occassionally when I know I'm the only car on the road, and the lane change alarm always shames me.