I posted this on facebook, but I think it deserves saying publicly as well:
Twitter is PUBLIC. Anyone can read it, and anyone can search it, and anyone can call you on the carpet for what you say. That's what PUBLIC means. If you don't want people or companies to search a PUBLIC forum and see what you say about whatever, then lock down your feed or, better yet, don't post anything. You have no reasonable expectation of "private conversations" when you post PUBLICLY to social media. BY DEFINITION.
So, teenagers and middle aged folks up in arms about corporations looking at their twitter feeds and anyone who doesn't really get social media, once and for all: If you don't want your privacy "invaded" by being held accountable for your tweets, DON'T TWEET.
Free speech does not mean that you have the right to post online or to social media without judgment or consequences. (just ask Dooce. Hey-oh, rimshot!) The first amendment protects your right to free speech: it says that you can say all the dumb shit you want (within reason, see the "fire in a crowded theater" supreme court case) and you won't be tossed in jail, NOT that you won't be suspended from school or fired from your job or roundly mocked. You have the right to say what you want, I have the right to think you're a dumbass, and vice versa. Judge away! That's what the internet is for!
Also, sweet peas, the internet is forever. Even if it's deleted, it's still out there somewhere. Ignorance or misunderstanding is not an excuse and not getting the internet and whinging about how you're a special snowflake who didn't know and therefore deserves a pass serves no one well. Privacy controls or self control. Your pick.
(All that said? Thank god there was no internet when I was a teenager. I can't only imagine the stupid shit I would have posted/said/did. )