What constitutes signal?
- Anything funny.
- News I want to know.
- Interesting links.
- Talking to me directly (esp. saying nice things to me or retweeting my tweets).
- Follow Friday tweets, thank you's, and any other random list of Twitter handles I don't know.
- Non-tweets, like "Good morning" or "Good night" or "Eating justice peas again."
- Spammy links to your blog, your book, etc.
- Most tweets generated by other applications (e.g. Goodreads progress reports).
- Lots of tweets at once, filling up my timeline.
Now understand, I'm not saying you should have no noise in your tweets. Everybody's got noise (I link to my blog and send retweets plenty). The important thing is to balance it out, or even signalify* the noise by making it funny or relevant.
And perhaps most importantly, there's the Relationship Factor. This is a measure of how well I know/like you. I'll tolerate a heck of a lot of noise from friends, people I enjoy talking to, or Nathan Fillion. In fact, the stronger our relationship, the more likely I am to interpret your "noise" as signal.
How do you build up the Relationship Factor? That's a different post.
I admit, it's a highly subjective algorithm, but it has to be. I'm not going to be interested in everyone's tweets. The point is, if you want to stay in people's timelines, pay attention to what most of your tweets are about. That way when you do have to pimp yourself, people will listen.
* Totally a word. Shut up.