Re: To the point...
It allows all of us to have followers and be celebrities.
Curiously, it seems all you need is a Twitter account and you start attracting followers. I have a couple of accounts. One I've only ever used for following a handful of people or occasionally following short-lived hashtags (e.g. for academic conferences I'm attending, in case there are pertinent announcements); the other is my work account, which exists solely to follow tweets from the company and co-workers. Though actually I haven't read either in months, when my workaround for Twitter's idiotic requirement of idiotic OAuth stopped working around. (I can't be bothered to fix it.)
I have never tweeted a single message, but between the two accounts I have a couple dozen followers, eagerly hanging on my utter silence. Some are people who know me in person and stumbled across one of my accounts. Some are people who followed me back after I followed them. Some are spammers and the sort of callow ninny who searches for Twitter accounts that might belong to a person who replied to a thread on LinkedIn, in an effort to expand their "social" network.
I don't think that makes me a celebrity, even by today's lax standards, but it's true that Twitter does make it very easy to attract faux attention. And that's what it's all about, isn't it?