In real life, there are many possible relationships you could have: close friends, less close friends, acquaintances, peers, colleagues, business associates, customers, fans, people you admire/people who admire you, random strangers. When you have a conversation in the real world, you tailor that conversation to whomever is listening. Audience matters. I wouldn't talk about my personal life or literary aspirations with my colleagues for the same reason I wouldn't try to initiate a conversation about microglia and potassium channels with my little sister.
On twitter, however, all audiences are created equal. The same people who are reading your book advertisements and political rants are also reading your conversations with your friends. And they can jump into that conversation whenever they want. If you're okay with that, then great.
But there are some things you should keep in mind:
-People don't always want to hear all of your conversations.
-People don't want to read EVERY. SINGLE. FIVE. STAR. REVIEW. OF. YOUR. BOOK.
-4square: Nobody needs to know where you are every second of the day. (And the people who do are probably not the ones with whom you want to interact.)
But what if people do want to know all about you and be your friend?
-Do you want to be this person's friend?
-Are you okay with this person joining in on your conversations?
(I will be honest. Sometimes I get a little jealous when I see people being BFFs on Twitter. But then when I do jump in and the original person responds to me, I never know if it's because that person likes what I had to say or if he/she is just being polite.)
Other things to remember:
-It's very easy for people who don't know you to take things you say out of context.
-You will have just as many (if not more) people who stalk you out of hate than people who stalk you out of love/admiration. Anything you say can be used against you.
If you really want to have conversations with your friends, there are a million other ways to do it. (facebook, skype, phone, instant messenger, email, etc) Or you can have separate twitter accounts.
Anyway, I'm not trying to whine or make any accusations in this post, but it is something that I felt was worth saying.