So I just hit my 400th tweet on @mdfranz but am scarcely up to 20 @frednecksec and I've learned a few things about how I like to use this addictive service in the past few months. And yeah (if you went there) my updates are protected, but more or that later.
When I was first started following people, I was annoyed by technical people (whose blogs I read or knew personally) that only tweeted about personal stuff, so I didn't follow them. I could give a shit about what what sort of decadent food they were cooking, what they were doing with their wife, or their kids accomplishments. But I was interested in 140 characters of wisdom on some technical/technology topic. If there was at least a 50:50 ratio of personal to professional context I kept following, otherwise I dropped them.
As Tom Peters would say, "you are your customers." Your personal brand is reflected in the those that you do business with and those that do business with you. The same applies to you twitter followers and folks you tweet with. If people that follow you tweet about stupid shit (to put it crudely, but probably characterizes some large % of tweets) that reflects poorly on you, since one of the first things I do when I follow someone (or someone follows me) is I check out the people they follow and their followers. It is the same principle as only connecting with "people you trust" on LinkedIn. On my public account I'm more open to follow somebody I don't know well enough or let anybody follow me, including spambots. But on my private account I approve all followers.
Frankly, a lot of stuff you tweet on has no business on public Internet (and all the various bots that follow you) where you shop, what you eat, the activities you do with your family, where you are geographically is none of the damn business of people that you don't really know, let alone twitter's public timeline. This is why I protect my updates on @mdfranz but don't on @frednecksec. Several weeks ago I registered for a demo version of some webapp and a product manager/sales person started following me. Creepy. I don't want sales people following me. And during the inauguration I wondered about how well Sprint's EVDO network would hold up and I had somebody in customer server ping me. She was nice/professional enough but I don't want that sort of interaction. I also don't want people I don't know to where I frequent.
Different Media for Different Messages
I've found that there are also two kinds of tweets: those personal, biased observations, and more objective factual statements that answer the original twitter question, "what are you doing?" More specifically what I'm am I reading that might be of interest to my readers. More reflective, opinionated tweets go on my personal account while the others (especially that are narrowly security related) go on my public account. This is the reason I've moved most of my high volume twitter lists (that mostly shared links and article) over to my public account. Public content stays public, private content stays private and I can also see on my public account when something I've read about, seen has already been tweeted on. I think RT is lame since the whole point is to post original content or content that reflects a certain perspective or range of interests.
So what Twitter client allows you to use multiple accounts at once, twhirl. Or use multiple browsers which is generally a good idea.