You are pretty much correct. But you're missing something important: Twitter moves so fast that anyone following a decent number of reasonably active people will just shrug and skip over the stuff you say that's not interesting.

So, for instance, if you're mutually following some of your friends, they may not have a damn thing to say about your thoughts on Java programming, but if you're both Apple users you may find yourself chatting with them during the next keynote. If you live in the same city you may find yourself organizing impromptu get-togethers over Twitter. Hell, a while back I was playing Dark Souls on a 360 without a net connection and tweeting about places I got stuck, and my followers offered me some pretty useful advice.

People who follow me are not interested in everything I have to say. They may not even see everything I have to say. But they are interested in ENOUGH of what I have to say that they're continuing to follow me.

Multiple accounts can help: I have a public one that I use a lot, my blog auto-tweets new posts to that one. I also have a private one that is only accessible to my friends (and to the private accounts of my friends); these accounts see us griping about day job stuff we don't want public, talking about our marijuana intake, our sex lives, all kinds of stuff we don't want to share with the whole world. There's also an account for my comic, that emits a tweet every time a new page or blog post goes up. I pretty much never tweet manually as that one! A good twitter client can make it a lot easier to maintain multiple accounts, but honestly? Just start with one, ask your friends if they have a twitter account and follow them, say whatever you feel an urge to dump into the void and see what happens. Here's a conversation I had this morning: https://twitter.com/egypturnash/status/480774881198358528

I find the best way to use Twitter is to stop thinking of it as a place you HAVE to be and turn it into a place you WANT to be. Twitter is where I chat with my friends and drop random nuggets of thoughts; I'll photograph something I think is interesting and make some comment about it that way, I'll mutter about some weird little social interaction I just had with a stranger and my friends will tell me that shit was fucked up or that it was perfectly normal and what rock have I been living under, I'll make some dumb joke and my friends will riff on it. Twitter is not where I Extend My Brand. Follow people, not entities. Not all people you know - I follow a bunch of leaders in my field (comics) - but if a bunch of them are your social circle, then Twitter becomes a place you WANT to go because it's where you can casually say hi to your friends and talk about what they're up to in an environment that welcomes both rapid responses seconds after the original statement, and ones a couple days later. (And I find that having it on my phone makes it much more attractive than having it stuck in a desktop machine - it's like I've got a bit of ALL MY FRIENDS present any time I want them around.)

Ultimately I kinda want to riff on Twitter's branding: Imagine a bunch of birds, hanging out in earshot of each other, singing to each other and working out just who's gonna mate with/intimidate/eat who. Follow your friends. They call it social media for a reason.